Application of the travel cost method to estimate the economic value

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Hacienda Pública Española / Revista de Economía Pública, 196-(1/2011): 37-63
© 2011, Instituto de Estudios Fiscales
Application of the travel cost method to estimate
the economic value of cultural goods: Blockbuster
art exhibitions*
EVA VICENTE**
PABLO DE FRUTOS
University of Valladolid
Recibido: Abril, 2010
Aceptado: Diciembre, 2010
Abstract
In recent years a growing number of studies have started to apply non-market valuation methods to es­
timate the economic value of cultural goods. The majority of these studies use stated preference tech­
niques, such as the contingent valuation method. This study discusses the application of the travel cost
method to estimate the economic value of a specific type of cultural good: special exhibitions. The em­
pirical work focuses on the touring exhibition the ‘Ages of Mankind’, one of the first and most repre­
sentative examples of a blockbuster art exhibition in Spain. This is the first time, as far as we know,
that this method has been applied to a large temporary exhibition and is one of the few applications of
this method in the valuation of cultural goods.
Keywords: Blockbuster arts exhibitions, non-market valuation, revealed preferences, travel cost
method, cultural economics.
JEL classification: H41, D60, Z11
1. Introduction
In recent decades temporary exhibitions have grown enormously in terms of frequency
and importance, leading to a boom in this type of cultural supply (Heilbrun and Gray, 1993;
∗ Authors gratefully acknowledge research funding for this study from the Directorate General for Cultural Herita­
ge, Regional Ministry of Culture and Tourism of Castile and Leon, Spain. We also wish to thank ‘Las Edades del
Hombre’ Foundation for permitting visitor surveys to be undertaken during the 2006 edition in Ciudad Rodrigo,
Spain. We are also very grateful to two anonymous referees for their helpful comments and suggestions.
** University of Valladolid, Department of Applied Economics. Eva Vicente. e-mail: evicente@eco.uva.es; Pablo
de Frutos. e-mail: pablof@ea.uva.es
38
EVA VICENTE AND PABLO DE FRUTOS
Frey and Busenhart, 1996; Frey, 2000; Johnson, 2003). Certain exhibitions, mainly destined
for a wide domestic and/or international audience, have become significant cultural events
attracting thousands of visitors. This is true for blockbuster exhibitions which, due to partic­
ular attributes, have reached a relevant position in the tourist and recreation choices of many
people.
Nevertheless, despite the success of these activities, their utility and social profitability
are still being debated. Policy makers and managers of cultural institutions are becoming in­
creasingly interested in evaluating and measuring the social benefits gained from these ini­
tiatives, although the few studies carried out to date have focused on measuring their eco­
nomic impact in terms of income and employment (Wall and Roberts, 1985; Stanley et al.,
2000; Skinner, 2006; Vicente et al., 2007), rather than the effects on social welfare by esti­
mating changes in visitor consumer surplus. Unlike the former approach, the latter focuses
on measuring the utility derived by individuals from the cultural goods or services or, in
equivalent terms, the value these goods or services are given from the maximum amount that
visitors are willing to pay to enjoy them.
The market is the usual mechanism through which individual preferences for different
goods and services are revealed, providing the necessary information to estimate their de­
mand, required prior to the valuation process. However, the public-good nature of many of
the values and services derived from cultural goods and the presence of externalities in their
production and consumption (Peacock, 1969; Netzer, 1978; Frey and Pommerehne, 1989;
Albi, 2003; Vicente, 2007) makes it impossible to measure them merely through the market,
forcing economists to seek alternative methods to assess their value (Cuccia and Signorello,
2002; Poor and Smith, 2004). The main difficulty is that the value currently attached to cul­
tural goods as well as the nature of the demand for their products and experiences are com­
plex phenomena, which go beyond their mere use value or direct consumption. These goods
or services also generate a further series of values referred to as non-use or passive-use, since
they are independent from their use or present consumption. These potential sources of util­
ity have been widely recognised and classified in the literature on the topic into three basic
categories: option value (the value which non-current users attribute to the possibility of
being able to consume cultural goods and services in the future), existence value (the value
attributed to the mere existence of the goods, regardless of any current or future use) and be­
quest value (the value citizens derive from knowing that the goods will be available for use
by future generations). Usually, none of these values are available in monetary terms. In the
case of use value, although cultural goods and services are often traded in markets, the con­
ditions under which they are usually provided –free of cost, subsidised or, in general, prices
not reflecting the cost of supplying them– means that the market proves insufficient as a way
to gauge true public preferences regarding such goods (Greffe, 1990; Mourato and Mazanti,
2002). Determining non-use value proves extremely complex, due to the intangible nature
and public good status, entailing the lack of markets where value can be estimated.
To overcome these difficulties, different techniques have been developed that allow the
economic value of these types of goods and services to be estimated. Such techniques, gen­
Application of the travel cost method to estimate the economic value of cultural goods
39
erally known as non-market valuation methods, have been successfully applied in other areas
in recent decades, particularly in the field of environmental resources. Despite the similari­
ties between these goods and cultural goods, application of these techniques in the latter in­
stance is relatively recent and comparatively few studies have ever been carried out (Pearce
et al., 2002), mainly using stated preference models, such as the contingent valuation
method1. In contrast, the application of techniques based on revealed preferences such as the
travel cost method (hereinafter TCM) has been very limited. This is due to the restrictive na­
ture of the assumptions upon which this technique is based, as well as the nature of cultural
goods and services, which limit the potential use of this approach (Greffe, 1990; Frey, 2000;
Ready and Navrud, 2002; Mourato and Mazzanti, 2002). Yet, the advantages gained from
working with revealed preferences, which allow modelling of consumer behaviour from data
obtained in non-contingent situations, support the use of this technique to measure the value
of cultural goods and highlight the need to undertake further research in this area (Boter et
al., 2005: 20).
In recent years, TCM has gained in importance as a valuation method in cultural eco­
nomics and has been applied in certain recent studies (Snowball, 2008: 78). This technique
has been used, for instance, in the areas of museums (Martin, 1994), the theatre (Forrest, et
al., 2000), and built heritage (Poor and Smith, 2004; Alberini and Longo, 2006; Parumog et
al., 2006; Chen et al., 2008). These studies apply the TCM to measure the use value of these
goods and services and in some instances, combined with other methods, to estimate their
total economic value.
In light of the foregoing, this study discusses application of the TCM to estimate the
consumer surplus associated with special exhibitions. We conducted an empirical study for
Kyrios, the thirteenth exhibition of the ‘Ages of Mankind’ (Las Edades del Hombre). These
exhibitions are a series of blockbuster exhibitions displaying religious art and are devoted to
the movable cultural heritage of the Catholic Church in the region of Castile and Leon
(Spain). As far as the authors know, this is the first time this method has been applied to a
large temporary or blockbuster exhibition2.
This article is outlined as follows: firstly, section two is dedicated to presenting the most
important characteristics of the study case; section three then moves on to discuss the travel
cost method with its associated problems and the source of data; section four is devoted to
analysing results from the demand model, estimated through the zonal travel cost method,
and the associated consumer surplus. Finally, a discussion and several conclusions of this re­
search are presented.
2. Study Case: Kyrios, the blockbuster exhibition of the
‘Ages of Mankind’ in Ciudad Rodrigo
Nowadays, large-scale special exhibitions or blockbusters are considered activities with
cultural and social relevance and prestige attached to them. Their welcome by the public,
40
EVA VICENTE AND PABLO DE FRUTOS
media impact and temporary nature make these cultural events highly attractive to promot­
ers, leading to an increase in the number thereof and securing the efforts and interests of var­
ious public and private institutions (Frey, 2000; Johnson, 2003). Their success lies in their
special characteristics, such as limited duration and the fact they are exceptional and unique
events3 (Belcher, 1994; Tobelem, 2005, 2006).
These kinds of cultural activities make art more accessible for the public to enjoy in two
main ways (Heilbrun and Gray, 1993; Skinner, 2006): a ‘concentration effect’ and a ‘distri­
bution effect’. They allow for the collection of a large amount of artwork based upon a
theme, an artist, movement or historical period; greater than could possibly be seen at one
time anywhere else. The display of the artwork together also has a powerful aesthetic impact
and creates a more lasting impression on visitors. These exhibitions allow cultural products
of large dimensions and great visual impact to be taken to places which are often far away
from large collections or museums, and are not themselves traditional cultural centres. Given
their nature, the temporary exhibitions attract experts and those interested in what is offered
on display, satisfying special or particular preferences and allowing specific demand niches
to be explored. These events are also featured by their ability to attract new audiences (Frey
and Meier, 2006), given that they manage to draw in people who have never before shown
an interest in art and would rarely visit a museum4 (Fernández and Prieto, 2004). This ‘pop­
ularisation’ of art, as Frey points out (2000: 93), may not be of much interest to certain artists
or art lovers, but it should be considered a remarkable achievement from the point of view
that it responds to individual preferences.
Given the variety of factors involved in their organisation, these ‘mega-exhibitions’
have complex production processes and are relatively expensive (Heilbrun and Gray, 1993;
Stanley et al., 2000; Skinner, 2006), generally requiring public support. The exhibitions also
rely heavily on collaborative and cooperative relationships, not only for financing but also
for communication purposes (Tobelem, 2005). Given their nature, the special exhibitions
provide potentially important economic benefits for the host institution and other agents involved, as well as for the area or region where they are held (Heilbrun and Gray, 1993; Frey,
2000; Tobelem, 2006), all depending on the magnitude and the scope of the exhibition (Vi­
cente, et al., 2007).
As with the majority of cultural goods and services, blockbuster exhibitions can be con­
sidered a quasi-public good: they are non rival goods –the visit to the exhibition is an ex­
perience which can be shared by a large number of people during the period it is shown and
many people can visit at once5 (Belcher, 1994) –and potentially excludable goods6. The
visit provides significant benefits to the user: the enjoyment or pleasure experienced while
viewing the exhibits (aesthetic benefits), entertainment (recreational benefits) and knowl­
edge (educational benefits). The value and quality of the experience provided by these types
of cultural activities are such that the public is willing to visit en masse and also pay for the
privilege. Together with their significant use values, blockbuster exhibitions are also ex­
pected to generate a non-use value, although the relative importance thereof is likely to be
much less than in the case of other cultural goods. A blockbuster exhibition is an exception­
Application of the travel cost method to estimate the economic value of cultural goods
41
al and unique cultural event of a limited duration, meaning that there is little point dis­
cussing the existence of option or bequest values in relation to goods of this nature which,
by definition, are linked to the availability of a good or service in the future. It is true, how­
ever, that some citizens may attach an existence value to such an activity, deriving mainly
from a feeling of pride and the image of prestige which hosting such an event confers on
the town or area where it is held. The existence value in this case would refer to the value
allocated to holding the exhibition (a cultural dissemination project) regardless of whether
or not it was to be visited. Such value differs from that allocated to the exhibited goods.
Conservation of such exhibits is independent from the exhibition and once the exhibition
has concluded they may be visited at their respective place of origin or where they are usu­
ally displayed.
The series of temporary exhibitions of the ‘Ages of Mankind’ is a clear example of suc­
cess in the diffusion of culture, the media impact and the social and economic repercussions
that such activities can have. This is evident in the 15 exhibitions held since 1988, which
have been open to the public for 100 months and have displayed approximately 3,700 pieces,
with accumulated number of visits exceeding nine million people (see Table 1). These fig­
ures endorse the exhibitions collectively as one of the most successful cultural events both
in Spain and on an international scale, considering their continuity in time and space, and
that rather than running out of steam they have managed to maintain the interest and expec­
tations of the public with each new exhibition.
‘Ages of Mankind’ is a series of religious art exhibitions, devoted to the movable cultur­
al heritage of the Catholic Church in Castile and Leon (Spain), and held in the region’s
cathedrals since 1988. They encompass religion and culture, are highly original in form and
purpose, and different to other temporary exhibitions held in Spain or abroad (García, 2000).
This project has been led by the diocese of Castile and Leon, through ‘Las Edades del Hom­
bre’ Foundation and relies on the financial support of different institutions and regional
agents including the regional government of Castile and Leon, different regional financial
institutions and local authorities of the cities and provinces where the different exhibitions
have been held. Further financing needs for the exhibitions have been met by income ob­
tained from the sale of catalogues and other such products. No income has been generated
from entrance fees as the visits are free of charge.
The objectives pursued with this series of exhibitions go beyond the exhibition of the
rich art of the Catholic Church in Castile and Leon. Through an innovative project of valori­
sation and diffusion of religious cultural heritage, a range of images, paintings, sculptures
and other objects have been sought out and presented in a secular framework to retransmit
their religious and cultural message. The fact that the exhibitions are more than just mere
artistic representations is one of the main reasons behind their initial success and has helped
to keep the project going over the years.
However, this is not the only reason for the success of the ‘Ages of Mankind’;
among other factors are the originality and the novelty of the initial project and the na­
42
EVA VICENTE AND PABLO DE FRUTOS
ture of the exhibits themselves. The ‘Ages of Mankind’ has marked a milestone in Spain
in terms of museum innovation. The design of the exhibitions breaks with traditional
methods of displaying artwork according to artistic style and following museum crite­
ria, using storyboards which display the work in context. The chosen pieces are select­
ed for each exhibition not only for their artistic value, but also for their facility to com­
municate the thread of ideas to the visitor providing form and content to each unique
exhibition. Other reasons for the exhibitions’ success include the historical and artistic
wealth of the cultural heritage of Castile and Leon, allowing a selection of exceptional
pieces to be chosen for each occasion, most of which have never been displayed before.
The use of the region’s cathedrals to display the exhibits also adds greater value to a
high quality cultural product, as are all the exhibited pieces. Other causes, not directly
linked to the exhibits, relate to the apt timing of the exhibitions within a context of
growing cultural demand and in particular the boom in cultural tourism, a trend in re­
cent decades. The final factor influencing the success of the exhibition to a great ex­
tent, is that entrance is free. Far from devaluating the exhibition, this has helped it to
fulfil its primary objective. Visitors were able to appreciate that exhibits belonging to
their common history and culture were on display and it did not therefore seem right to
charge an entrance fee. Another objective pursued by the organisers of the ‘Ages of
Mankind’ has also been achieved, namely that the public would see exhibited pieces as
something belonging to them, identifying with them, and valuing them as their own
property (García, 2000).
Twenty years of the ‘Ages of Mankind’ has allowed this series of exhibitions to be re­
ferred to as the largest cultural project (in the area of exhibition policies) undertaken in
Spain, considering the extraordinary length of time it has been running (Vicente et al., 2007).
However, in the beginning this series of exhibitions was designed with more modest aims:
the initial project solely contemplated three large exhibitions which would be held in the
cathedrals of Valladolid, Burgos and Leon, respectively.
The repeated success of the ‘Ages of Mankind’ led to the initial project being continued
after it had originally finished, with the creation of an identically-named foundation commit­
ted to organising an exhibition in each diocese of the region which had not yet held one of
the exhibitions. During the first stage of the project a total of 13 exhibitions were held in
Castile and Leon and two in Antwerp and New York. Once the ‘Ages of Mankind’ exhibi­
tions had passed through the cathedrals of the region, a new stage of the project was started,
which took the exhibition to other locations in Castile and Leon, using new exhibition spaces
such as basilicas and co-cathedrals, starting in Ponferrada with the exhibition ‘Yo, camino’.
The main characteristics and results of the exhibitions held to date are detailed below in
Table 1.
The exhibition used for this study, ‘Kyrios’, was the thirteenth exhibition of the ‘Ages of
Mankind’ series, concluding a significant stage of this cultural project which had been tour­
ing the different cathedrals of Castile and Leon since 1988.
43
Application of the travel cost method to estimate the economic value of cultural goods
Table 1
THE ‘AGES OF MANKIND’ EXHIBITIONS (1988-2010)
Exhibitions
Location
El arte en la Iglesia de Castilla y León
Valladolid
Libros y documentos en la Iglesia
Burgos
de Castilla y León
La música en la Iglesia de Castilla
León
y León
El contrapunto y su morada
Salamanca
Flandes y Castilla y León
Antwerp
La ciudad de seis pisos
El Burgo de Osma
Memoria y esplendores
Palencia
Encrucijadas
Astorga
Remembranza
Zamora
Time to Hope
New York
El Árbol de la Vida
Segovia
Testigos
Ávila
Kyrios
Ciudad Rodrigo
Yo Camino
Ponferrada
Paisaje Interior
Soria
Total
−
Year
Duration Exhibition Number
(months) displayed of visits
1988-89
5
209
1,050,000
1990
6
482
500,000
1991-92
1993-94
1995
1997
1999
2000
2001
2002
2003
2004
2006
2007
2009-10
10
11
3
7
7
6
7
2
8
7
6
7
8
219
220
182
182
305
305
374
100
301
278
200
131
208
980,000
1,303,000
95,000
458,757
612,000
460,000
510,000
205,207
858,977
859,859
550,253
407,040
407,377
−
100
3,696
9,257,470
Source: Created by us based on data from “Las Edades del Hombre” Foundation website.
Kyrios was organised and coordinated by two institutions: ‘Las Edades del Hombre’
Foundation and the regional government, through the ‘Siglo para las Artes’ Foundation in
Castile and Leon. The exhibition relied on funding from both institutions together with spon­
sorship funds from Caja España savings bank and the Historic Heritage Foundation of
Castile and Leon channelled through the ‘Siglo para las Artes’ Foundation. In addition, ad­
vertising and marketing expenses were supported by the Society for Promotion of Tourism
in Castile and Leon (Sociedad de Promoción del Turismo de Castilla y León). The total cost
of Kyrios amounted to more than 3.7 million euros.
The exhibition opened on 9 June 2006 for a period of six months, until 10 December
2006. The exhibition reflected its title Kyrios (Lord) and the exhibition’s storyboard was or­
ganised accordingly in five chapters, concentrating on the figure and life of Christ. Two hun­
dred pieces from the eleven dioceses of Castile and Leon were displayed, in particular those
from the diocese of Ciudad Rodrigo, as well as eight pieces from Portuguese civil and eccle­
siastical institutions, 90% of all pieces never having been shown before. The exhibition
spanned the entire period from the 10th century to the 20th century, and included artists such
as Gregorio Fernández, Diego and Gil de Siloé, Pedro de Mena, Juan de Arfe, Fernando Gal­
lego, Pedro Berruguete, Luis de Morales, Luca Giordano and Alonso Cano, among others.
44
EVA VICENTE AND PABLO DE FRUTOS
As in many of the previous exhibitions, the number of visits exceeded initial forecasts,
the final figure reaching 550,253 visits. Kyrios became the seventh most visited exhibition
of the eleven held in the cathedrals of Castile and Leon, with visitor numbers surpassing
even those of exhibitions held in provincial capitals such as Zamora and Burgos.
3. Methods and data
3.1. Methods
These are a number of reasons why TCM is the approach selected to estimate the con­
sumer surplus associated with the cultural visits to the Kyrios exhibition. Firstly, it is one of
the most popular valuation techniques for measuring the value of a non-market resource (In­
hyuck, 2007). Secondly, TCM is a suitable method to assess temporary exhibitions since,
given their characteristics (a unique event within a limited timeframe) the use value dominates
as opposed to other cultural or heritage goods, in which the non-use value prevails and for
which it is preferable to use other methods such as the contingent valuation method7. Finally,
its application is cheaper than other methods, in particular contingent valuation methods.
This method has been developed from a suggestion made by Hotelling (1947). This au­
thor suggested using the travel cost incurred by individuals when visiting a recreation site as
an implicit price for the services of that site. Exploiting the empirical relationship between
increased travel distances and associated declining visitation rates would allow for the esti­
mation of the demand relationship. In this way, the Marshallian demand curve for the recre­
ation service can be estimated and appropriate consumer surplus measures calculated and
thus provide a basis for comparing them with the cost of their supply.
Two major variants of the TCM are the zonal travel cost method (ZTCM) and the indi­
vidual travel cost method (ITCM). A general reduced-form demand function relates visita­
tion rates (VR) to travel cost (TC) and other relevant variables (Xi) and can be specified as:
VRi = α + β1TCi + β2X2i + β3X3i + ... + εi
[1]
where α is the intercept, the β’s are the regression parameters and εi is the error term indi­
cating each zone or individual (Perman et al., 1999).
In the ZTCM, the area surrounding the recreation site is divided into various zones. Each
zone has an average travel cost according to its distance from the site (Garrod and Willis,
1991). The visitation rate per zone, in a given time period, can be estimated using the aver­
age travel cost. Several authors have applied this version to estimate the demand relationship
(Englin and Bowker, 1996; Bateman et al., 1999; Bennear, 2005; Inhyuck, 2007). However,
this approach has two significant limitations (Ward and Bell, 2000). Firstly, there is the dif­
ficulty in accounting for the effects of travel time on individuals and secondly, the aggrega­
tion and averaging process required to estimate zonal values make certain demand determi­
Application of the travel cost method to estimate the economic value of cultural goods
45
nants, particularly the socioeconomic variables, statistically non-significant. In fact, there is
a loss of information efficiency.
For its part, ITCM uses survey data from individual visitors to link the demand of pub­
lic goods to its determinants. The number of trips made by an individual over a given peri­
od of time may be estimated by calculating how far the visitor must travel to get to the site,
the amount of time spent travelling, travel and on-site expenses, their income and other so­
cioeconomic characteristics. Therefore, this method allows the amount of visits purchased at
different prices to be calculated. Two advantages of ITCM are that it follows conventional
methods used by economists to estimate economics values based on market prices, and it
also relies on what people actually do rather on what people say they would do in hypothet­
ical situations (Bell and Leeworthy, 1990). For these reasons and the weak theoretical foun­
dation of the behavioural patterns in aggregate demand models, this version is preferred over
the ZTCM (Bhat et al., 1998; Buchli et al., 2003; Nillesen et al., 2005, etc.). Moreover, eco­
nomic theory shows individual models to be superior to zonal models (Fletcher, et al., 1990).
In this sense, empirical studies provide mixed results. For example, the ZTCM is considered
more appropriate to estimate consumer surplus when visits are uniformly distributed, al­
though ITCM is considered more suitable for the case of multiple-destination due to the dif­
ficulty of obtaining the site-specific travel cost estimates (Cook, 2000).
As the relevant literature highlights, one of the main problems preventing the use of
ITCM is that individuals very often make just one visit to the good valued, the estimated de­
mand curve thereby reflecting relatively few observations other than the value one for the
number of trips variable (Riera, et al., 1994; Saz and Pérez y Pérez, 1999, etc.). Such is the
case with blockbuster exhibitions which, because of their limited duration and special event
nature, receive very few repeat visitors. This is reflected in our case study, Kyrios, where
only 6% of interviewees had visited the event more than once. This means that the demand
function, estimated through the individual version of the model, does not explain visitor be­
haviour sufficiently and may not be used to calculate consumer surplus. As a result, in order
to estimate the value of visitor benefits associated with this cultural event, a zonal travel cost
model was chosen for the present study8. This decision should not entail any major implica­
tions, since this methodology uses relatively straightforward demand models that, given cer­
tain research objectives, can indeed perform as well as individual models (Hellerstein, 1995).
We believe that this approach is appropriate as visits are uniformly distributed among Span­
ish provinces and only visitors who declared that the basic reason or purpose for their jour­
ney was to visit the ‘Ages of Mankind’ exhibition were selected from the sample. In this way,
data used in this study are limited to planned visits, in which the travel cost does not involve
multiple purposes. This does not pose a great problem, as one of the characteristics of these
types of exhibition is actually to exercise substantial influence on willingness to travel
(Boter, 2005: 25), the truncation percentage of the sample therefore being fairly small9.
However, there are a number of problems that may arise when applying TCM, two of
which are briefly discussed here. The first is the choice of a functional form used to estimate
the demand curve. The economic theory of constrained optimisation with weak complemen­
46
EVA VICENTE AND PABLO DE FRUTOS
tarity does not imply any particular functional form for the trip generating equation. Given
no a priori guidance, the functional form is decided according to which fits the data better.
This decision has important implications for the results obtained and affects both the expect­
ed value and variance of consumer surplus estimates (Ziemer et al., 1980; Hanley, 1989;
Adamowicz et al., 1989; Ozuna et al., 1993).
Three functional forms were used to estimate the econometric model of visitor demand:
linear, semilog, and exponential specification functions. Linear models are the most common­
ly used on estimations when using ordinary least square (OLS) regression. No variables need
to be transformed, thus minimising potential coding errors. They are also easy to interpret for
policy makers analysing visitor rates. However, linear models have been less popular over the
last 20 years of published research in TCMs because the goodness of fit is poorer than nonlinear forms (Ward and Beal, 2000). This is particularly the case where there are few visits at
very high prices and many visits at near-zero prices. In our case, the linear function had the
least adjusted R2 compared to the other two models, leading us to reject this approximation.
Semi-log models, where the dependent variable is transformed by taking the natural loga­
rithm, are commonly used in literature, such as by Ziemer, Musser and Hill (1980), Vaugh­
an, et al. (1982), Strong (1983) or Willis and Garrod (1991). This specification shows the best
adjusted R2, although the test for the presence of heteroscedasticity rejects the null hypothe­
ses of homoscedasticity, which would bias parameter variance estimates and lead to incorrect
statistical conclusions. We therefore also rejected this specification. The third specification
presents the second best adjusted R2 after the semi logarithmic model. The exponential spec­
ification for the Clawson and Knetsch model was thus selected.
The second widely discussed aspect of TCM is the specification of the monetary price
of the recreation trip. There are four kinds of travel cost that could be used in a TCM study
(Ward and Beal, 2000): firstly, taking account of only the cost of the petrol (petrol cost); sec­
ondly, other expenses generated by the car such as wear and tear, insurance and so on may
also be added (full car running cost); we may also add other expenses incurred during the
trip such as meals and accommodation (out-of-pocket cost); finally, the travel time and recre­
ational experience may also be taken into consideration (travel time cost). In all these cases,
consumer surplus may vary significantly depending on the decisions taken, possibly leading
to the belief that the measures obtained using this valuation method include judgements
made by those conducting the analysis. This is perhaps the main criticism levelled at this ap­
proach by many authors, the most critical probably being Randall (1994: 93-95), who argues
that ‘the resulting travel costs and welfare estimates remain artefacts of the travel cost ac­
counting and specifications conventions selected for imposition’ and ‘the best we can expect
is ordinally measurable welfare estimates’.
In order to minimize the effect of the monetary travel cost specification on the estimat­
ed welfare measures and thus be able to analyse the sensitivity of surplus measures to the pe­
cuniary cost specification, it was decided to use the four options posited in the literature.
Specifically, the following types of travel cost were designed. Firstly, only the cost of the
petrol was taken in to account (TCpetrol), calculated as the consumption of an average vehi­
Application of the travel cost method to estimate the economic value of cultural goods
47
cle weighted in terms of the characteristics of the total number of cars in the country and
prices of different car fuels. Although not the most common option in the literature, it is the
most prudent. Secondly, in addition to the petrol cost, it was decided to take account of other
expenses generated by the vehicle (TCfullcar), including all the expenses incurred by the ve­
hicle during the trip in terms of fuel, wear and tear, insurance and so on. Thirdly, added to
these are the other expenses linked to visiting the event (TCoutofpocket), specifically accom­
modation and meal expenses incurred by the visitor as a result of making the trip.
Including travel time as an element of travel cost is a more controversial issue (Bock­
stael et al., 1987; Larson, 1993; Azqueta, 1994, etc.), concerning which there is no agree­
ment. To gauge its effects on measures of surplus, estimations that included the time taken
up in travel were included separately. Specifically, a percentage of the hourly wage as an ap­
proximation of the opportunity cost of the time taken up in travel was considered, following
the approach employed by most authors. Given the lack of agreement regarding the value to
be applied, the two most common found in the literature are used. Firstly, 20% of the hourly
wage as proposed by Garrido et al. (1996), Parumog et al. (2003), etc., and secondly, 50%
of the hourly wage as proposed by Cesario (1976), Riera (1997), etc.
Combining various choices of travel costs and the inclusion or otherwise of travel time
gave rise to nine specifications of the demand function that were estimated as follows:
Ln (VRi) = α + βi * 1/TCi + β2 * INCOMEi + εi
[2]
where i-zones are Spanish provinces, equivalent to two digits statistical division of the Na­
tional Statistics Institute (Spanish Statistical Office). VRi are the visitation rates of area i, de­
fined as visitation per 1,000 inhabitants and calculated using the following formula:
VRi =
Vi + 1000
Pi
[3]
TCi are the vehicular travel costs, in current euros, based on several cost specifications
between the capital of area i and the study site. This variable is expected to be negative, in
the sense shown by economic theory. INCOMEi is the per capital gross domestic product of
the i areas, in thousand current euros, used to display the effect of level of income on the de­
mand function. Therefore, the expected sign of this variable would be positive in the sense
shown by economic theory.
The estimated travel costs regression coefficients can be used to determine the value of
the ‘Ages of Mankind’ exhibition in Ciudad Rodrigo in terms of consumer surplus. Using an
evaluation technique, often known as the Hotelling-Clawson approach, the travel cost coef­
ficient is used as a measure of sensitivity of visitors to added cost, such as an entrance fee
(Clawson and Knetsch, 1966). If ef is the added cost, equation (2) becomes:
β̂1
+ε i
α̂ +
V̂i *1000
= e (TC+ef )i
Pi
[4]
48
EVA VICENTE AND PABLO DE FRUTOS
^ the es­
^ and β
where V^i is the estimated numbers of annual trips from area i to Kyrios and α
1
timated regression parameters. We can refer to the relationship in equation (4) as the Mar­
shallian or uncompensated demand curve which includes the income effect of a price
change. Integrating this equation results in an estimate of the Marshallian consumer surplus
(MCS) in the absence of an entrance fee10 (Anex, 1995). This estimation could be an accu­
rate approximation of the individual visitor’s welfare under the assumption of a free access
situation. Equation (4) can be integrated as follows:
MCS
=
max tc α̂+ β̂1 dTC
e TC
∫
[5]
min tc
Where mintc is the travel cost of reaching the closest area i and maxtc is the cost at which
no trips are demanded, also known as the choke price. Given the characteristics of the esti­
mated demand function, the choke price would be infinite. Calculation of the Marshallian
consumer surplus would not be possible using an infinite choke price. To solve this problem
travel cost was replaced by the maximum cost possible to access the zone from within Spain.
This decision has been justified by it being unlikely that trips are demanded from a greater
distance.
The mathematical solution of the integration process returns the following formula to
calculate the MCS of visitor to Kyrios (Frutos et al., 2009):

max tc ∞ 
β̂1n +2
1
1
 


MCS
=
e α̂ (max tc −
min tc) +
β̂1 ln
+
∑ 
−
 
[6]
n
+1
min tc n =0 
max tc n+1 


 (
n +
2)!(n +
1)

min tc

Once the travel costs have been discounted (NETMCS), the net Marshallian consumer
surplus is calculated. The value could be considered as a safe approximation of the maxi­
mum willingness to pay for entrance to the Kyrios exhibition. In this instance, the demand
function is integrated between the atc and maxtc limits, where atc is the weighted average
actual travel cost. This could be considered as the maximum entrance fee which would elim­
inate visitor satisfaction (whereby they would not mind if they did not visit the exhibition).
3.2. Data
Aggregation (i areas) was selected on a provincial level because in Spain there is no re­
liable statistical information to lower aggregations, except on a municipal level, although
disaggregation occurs to such an extent that it does not respond to the focus of the study.
Higher aggregation was possible at one digit statistical division of the National Statistics In­
stitute (Spanish Statistical Office) equivalent to Autonomous Communities level, but this ag­
gregation was rejected due to the loss of information efficiency.
The total visitation Vi calculation was based on data from a survey carried out at the ex­
hibition during the period it was open to the public, using simple random sampling. To pre­
Application of the travel cost method to estimate the economic value of cultural goods
49
serve the randomness of the sample, the surveys were carried out on pre-arranged days and
times, alternating between a.m. and p.m. sessions, as well as weekdays and weekends to re­
flect all possible types of visitor. The surveys were performed by a group of four interview­
ers specifically trained in directly interviewing visitors leaving the exhibition. The surveys
were carried out between July and November 2006. Prior to carrying out the surveys a pre­
test was performed in June, which served to make slight adjustments to the questionnaire.
The questionnaire comprised 32 questions covering different aspects related to the visit and
its valuation, the socio-demographic profile of visitors, travel details, visitor spending and
reason for the trip. The sample consisted of 1,125 questionnaires, after incomplete or non­
valid surveys had been removed.
The sample was truncated to calculate this variable as follows. We first selected inter­
viewees who had incurred some travel cost, which meant removing residents of Ciudad Ro­
drigo from the sample. As a result, only those who had travelled to visit the exhibition were
considered to be visitors11. Secondly, we selected visitors who had travelled in their own ve­
hicles and excluded those who had travelled by coach as it proved impossible to attribute any
access cost to them12. Finally, we selected those whose visit to the exhibition had been the
basic reason or purpose of their journey.
TCpetroli were calculated for a range of different types of cars under the assumption that
the type of vehicle a person owns and the price of the petrol does not depend on the zone of
origin and that costs per kilometre are the same across all zones. The weighted-average run­
ning cost in current euros was calculated using data from the Ministry of Industry, Tourism
and Trade on distances and prices of petrol (MITT, 2006). TCfullcari was calculated using
the same hypotheses, where the mean cost chosen per kilometre was that paid by various
Spanish administrative bodies to their employees who are required to travel for work reasons
using their own vehicle (0.19 euros). This covers all expenses incurred in terms of petrol,
wear and tear, insurance, etc. generated by the vehicle during the trip. TCoutpocketi was cal­
culated by adding to the above mean expenses for accommodation and meals stated by vis­
itors during the survey.
The population per zone i (Pi) and per capita domestic gross product of i zones (INCOMEi ) were collected from the National Statistics Institute (NSI, 2006). Provincial hourly
wage was calculated using data taken from the Tax Authorities (AEAT, 2006) and National
Statistics Institute (NSI, 2000).
4. Results
The results of the ordinary least squares estimation of the demand models, described by
equation (2) for all travel cost specification, are presented in Table 3.
The models were evaluated using several criteria, including explanatory power (adjust­
ed R2) and significance (F-value). In the first case, the explanatory power proved very high
50
EVA VICENTE AND PABLO DE FRUTOS
for all models with an adjusted R2 between 0.763 and 0.697. In the second case, F-ratio value
indicated that all models were significant, particularly at the 1% level.
As regards the price or travel cost coefficient estimates for each of the nine specifica­
tions, these were consistent with demand theory, in that the quantity of visitors per 1,000 in­
habitants in the area was inversely related to price or travel cost. Intercepts and travel cost
coefficients were significant at the 1% level. In relation to provincial per-capita income, the
coefficients were significant at 1% level and the signs are positive, in line with consumer be­
haviour.
The models were tested for heteroscedasticity because travel cost models with unequal
populations often lack homoscedasticity, caused by the difference in visitation rates from
zones with larger populations being greater than in zones with smaller populations (Bowes
and Loomis, 1980; Vaughan, et al., 1982). This problem is also common when there are vari­
ations in visitation rates between zones (Christensen and Price, 1982). The correlation be­
tween dependent variables predicted adjusted values and standardised residuals regression,
using Pearson’s correlation coefficient, were insignificant at the 95% significance level for
all models. Heteroscedasticity is not, therefore, considered a problem for this analysis.
Models were also tested for autocorrelation, using the Durbin-Watson test, and residu­
als normality absence, using the Kolmogorov-Smirnov test with the standardised residuals
sample. The applied test rejected the presence of these problems, and so models are believed
to be valid for prediction making and the Marshallian consumer surplus is calculated in
terms expressed in formula number 6.
Table 2
VARIABLE SUMMARY STATISTICS (EQUATION 2)
Variable name
LnVR
1/TCpetrol
1/TCpetrol(20%wage/hour)
1/TCpetrol(50%wage/hour)
1/TCfullcar
1/TCfullcar(20%wage/hour)
1/TCfullcar(50%wage/hour)
1/TCoutofpocket
1/TCoutofpocket(20%wage/hour)
1/TCoutofpocket(50%wage/hour)
INCOME (in thousand euros)
Dependent variable LnVR.
Source: Own elaboration.
Mean
Standard
deviation
–2.4767
0.0175
0.0140
0.0108
0.0074
0.0067
0.0059
0.0051
0.0048
0.0043
18.8033
1.2556
0.0131
0.0100
0.0810
0.0055
0.0049
0.0043
0.0031
0.0029
0.0027
3.8301
Upper
boundary
Lower boundary
Value
Upper
boundary
Lower boundary
Value
Upper
boundary
Lower
boundary
Value
Statistic
value
(t-value)
Dependent variable LnVR.
Source: Own elaboration.
F–statistic
R–squared
Adjusted R–squared
Significance level
Durbin–Watson
INCOME
1/TC
Intercept
Variable
0.159
47.144
0.718
0.703
99%
2.049
48.205
0.723
0.708
99%
2.029
0.099
(3.356
0.093
(3.198)
0.152
0.039
0.034
125.622
103.832
(9.655)
83.256
(9.763)
100.535
82.041
65.978
–4.542
–5.796
(–9.366)
–5.686
(–9.347)
–4.453
–7.050
20%
wage/hour
–6.919
Only
petrol
TCPetrol
45.919
0.713
0.697
99%
2.066
0.165
0.104
(3.482)
0.044
163.054
134.460
(9.528)
105.866
–4.616
–5.892
(–9.353)
–7.168
50%
wage/hour
48.205
0.723
0.708
99%
2.029
0.152
0.093
(3.198)
0.034
238.770
197.734
(9.763)
156.697
–4.453
–5.686
(–9.347)
–6.919
Only
fullcar
47.743
0.721
0.706
99%
2.038
0.155
0.096
(3.276)
0.037
263.923
218.382
(9.716)
172.840
–4.497
–5.739
(–9.361)
–6.982
20%
wage/hour
TCfullcar
47.117
0.718
0.703
99%
2.050
0.159
0.099
(3.362)
0.039
301.563
249.241
(9.652)
196.919
–4.546
–5.801
(–9.368)
–7.055
50%
wage/hour
60.529
0.776
0.763
99%
1.615
0.146
0.091
(3.385)
0.036
438.548
370.080
(10.973)
301.611
–4.902
–6.081
(–10.475)
–7.259
60.355
0.775
0.762
99%
1.645
0.148
0.094
(3.467)
0.039
465.105
392.402
(10.957)
319.700
–4.922
–6.105
(–10.483)
–7.287
Only
20%
outofpocket wage/hour
TCcoutofpocket
59.735
0.773
0.760
99%
1.686
0.152
0.096
(3.553)
0.041
504.444
425.257
(10.901)
346.051
–4.939
–6.129
(–10.459)
–7.318
50%
wage/hour
Table 3
ORDINARY LEAST SQUARES ESTIMATE FOR KYRIOS MODELS: SUMMARY MODELS AND DEMAND PARAMETERS
Application of the travel cost method to estimate the economic value of cultural goods
51
52
EVA VICENTE AND PABLO DE FRUTOS
The results of the integration process between minimum-maximum and actual-maxi­
mum travel cost are presented in Table 4. Consumer surplus range varies between the
27.85 € (TCpetrol without travel time) to 93.23 € (TCoutofpocket and travel time 50%
wage per hour) where the mean for all travel cost specifications reaches a value of 63.64 €.
Based on these data, total benefits from the event could be estimated as approximately 30
million euros, with a variation ranging between 13 and 44 million depending on the cost
specification used.
With regards to the net Marshallian consumer surplus (NMCS), visitors would have
been willing to pay a mean entrance fee of 7.72 euros to visit the exhibition, with a range be­
tween 3.36 euros (TCpetrol without travel time) and 10.34 euros (TCoutofpocket and travel
time 50% wage per hour). Hypothetically speaking, the organisation of this event could have
obtained revenue, based on entrance fees, between 1.8 and 4.8 million euros depending on
the cost specification used, with a mean of around 3.6 million euros.
As regards the sensitivity of the surplus value to the specification of the cost function,
the highest specifications (TCoutofpocket) almost triple the most conservative (TCpetrol),
the former being 2.5 times greater than the latter. Specifically, without taking account of the
travel time value, the differences are identical to those reported by English and Bowker
(1996), where the highest surplus values are 2.79 greater than the lowest. The studies of
Pérez y Pérez et al. (1996a) or Saz and Pérez y Pérez (1999) follow a similar line, the mean
values being 3 and 2.6 times greater. Differences are lower in the studies of Pérez y Pérez et
al. (1996b) or Riera et al. (1994), ranging between 1.9 and 1.5 respectively.
As regards the impact of including travel time cost in the surplus value, sensitivity is
lower, values ranging between 7% and 50% depending on the cost specification and percent­
age of hourly wage used. This sensitivity is lower than that obtained by other authors such
as Garrido et al. (1996), whose findings show that the surplus value may be twice as great
depending on the percentage of hourly wage used in the cost function.
Estimation of the elasticities of the exhibition demand provides interesting information
related to the response of visitors to variables such as price and income (see Table 5). The
price elasticity of the demand function for Kyrios is close to one (-1.196). This demand func­
tion of unitary elasticity shows that the increase or decrease in the number of visitors to the
exhibition is proportional to the increase or decrease in the travel cost. Therefore, an increase
in access cost for the visitor, by increasing a hypothetical entrance fee forming part of the
travel cost, would reduce the number of visitors in the same proportion and would not affect
revenue significantly. It should be noted however, that entrance fees usually represent a rel­
atively small part of the total costs which are involved in this type of activity13 (O’Hagan,
1995; Albi, 2003; Prieto and Fernández, 2006), so it is likely that although demand is sensi­
tive to total price, i.e. expenditure for the overall trip, it may be less sensitive to changes in
entrance fees (Blattberg and Broderick, 1991; Frey and Meier, 2006)14. This low elasticity
would provide a margin for special exhibition managers to increase revenue by raising entrance fees (Frey, 2000)15.
TCoutofpocket
TCfullcar
TCpetrol
TCoutofpocket
TCfullcar
TCpetrol
TC
specification
Source: Own elaboration.
NETMCS
MCS
Individual
visitor welfare
measurement
maxtc
154.6
193.2
250.97
367.08
405.72
463.49
463.72
495.72
553.49
MCS MEAN
154.6
193.2
250.97
367.08
405.72
463.49
463.72
495.72
553.49
NETMCS MEAN
mintc/atc
14.1
17.74
23.25
33.44
37.1
42.61
62.44
66.1
71.61
77.83
97
125.76
184.86
204.02
232.78
250.8
270.1
299.05
Travel Time
Only petrol
20% wage/hour
50% wage/hour
Only fullcar
20% wage/hour
50% wage/hour
Only outofpocket
20% wage/hour
50% wage/hour
Only petrol
20% wage/hour
50% wage/hour
Only fullcar
20% wage/hour
50% wage/hour
Only outofpocket
20% wage/hour
50% wage/hour
1.88
2.35
3.88
4.46
4.94
5.64
4.32
4.65
5.31
4.16
8.72
10.37
12.82
20.74
21.56
24.83
23.37
25.22
28.05
19.52
Minimum
3.36
4.24
6.98
7.97
8.86
10.18
8.47
9.1
10.34
7.72
27.85
33.17
40.83
66.39
70.19
79.36
77.76
83.99
93.23
63.64
Mean
Table 4
INDIVIDUAL VISITOR WELFARE ESTIMATES FOR KYRIOS (in current euros)
6.01
7.66
12.57
14.27
15.92
18.4
16.66
17.82
20.15
14.38
103.25
123.33
151.96
246.61
263.8
295.2
286
309.57
344.38
236.01
Maximum
Application of the travel cost method to estimate the economic value of cultural goods
53
54
EVA VICENTE AND PABLO DE FRUTOS
Table 5
ELASTICITIES FOR KYRIOS DEMAND MODELS
TC specification
TCpetrol
TCfullcar
TCoutofpocket
Travel Time
Price elasticity*
Income elasticity*
Only petrol
20% wage/hour
50% wage/hour
Only fullcar
20% wage/hour
50% wage/hour
Only outofpocket
20% wage/hour
50% wage/hour
–1.0696
–1.0704
–1.0692
–1.0696
–1.0703
–1.0707
–1.4756
–1.4528
–1.4220
1.7487
1.8615
1.9555
1.7487
1.8051
1.8615
1.7111
1.7675
1.8051
MEAN
–1.1967
1.8072
* Elasticities evaluated at mean.
Source: Own elaboration.
Demand price elasticities hardly varies with regard to the specification of chosen travel
cost, the values obtained proving virtually identical for the specifications TCpetrol and TC­
fullcar. If we take account of all the expenses (TCoutofpocket), the demand function becomes slightly more elastic, with values approaching –1.4. This might be because the greater
the distance which visitors have to travel, the proportionally more other expenses linked to
the trip, particularly accommodation and meals, are likely to rise. This would lead to a sharp­
er reduction in the participation rate due to increased travel costs. The value of price elastic­
ity do not vary either if we take into consideration or not the cost of travel time value and
the percentage of hourly wage chosen.
The income elasticity is positive (1.807), indicating that demand for this good can be
considered normal, in line with empirical studies carried out to date in other areas of the cul­
tural sector which also usually give positive results for this variable (Throsby, 1994; LévyGarboua and Montmarquette, 2002; Albi, 2003; Seaman, 2006). Income elasticity above one
indicates that spending on such activities increases proportionately more in relation to the increase in visitor income. Temporary exhibitions would therefore be considered luxury
goods, which are consumed regularly by consumers with medium to high incomes (Heilbrun
and Gray, 1993). The value of income elasticity obtained supports the positive growth ex­
pectations for this sector (Frey and Meier, 2006) and also relates to the boom in demand for
this type of activity with the increase in real income which has occurred in recent decades
(Frey, 2000).
In this case, there are again no differences depending on the cost specification chosen.
Values are thus very similar for the three kinds of travel cost used. In this case, the main dif­
ferences are in the travel time value, where there is a positive relation between the elastici­
ty value and time cost. In other words, the greater the opportunity cost of time measured in
hourly wage, the more elastic to income is the demand function.
Application of the travel cost method to estimate the economic value of cultural goods
55
5. Conclusions and discussion
The main objective of this study was to investigate the potential of the travel cost
method in measuring the social benefits derived from cultural goods by its application to a
specific case study: blockbuster art exhibitions. Despite the growing significance of such
cultural activities, to date no study has approached their economic valuation by estimating
demand function and calculating the consumer surplus associated with the provision of such
goods. The authors believe that a knowledge of the demand function is fundamental for the
management of this kind of cultural event. Its estimation enables calculation of individual
visitor welfare under the assumption of free access in the form of Marshallian consumer surplus (MCS) or the maximum willingness to pay, through a hypothetical entrance fee that increases travel costs, in the form of net Marshallian consumer surplus (NETMCS). In the case
of Kyrios, the mean MCS reaches a value of 63.64 € per visitor and the NETMCS 7.72 €
per visitor.
One finding to emerge was the sensitivity of consumer surplus value to the monetary
cost specification. In summary, this research indicates that selection of travel cost prices is
important in estimating consumer surplus. Choosing an incorrect definition can lead to a
mis-specified price variable and a biased surplus estimates. This is extremely important
when using TCM as a tool to calculate admission prices to such events, as this value might
prove a key component in access cost and have a major impact on the decision to visit. In
any case, as most authors advise, there is a need to be cautious and to choose the most con­
servative estimations when these are used as a management tool for attribute valued.
The values obtained in the present study are higher than those reported by other authors.
For example, using ZTCM, Prayaga et al. (2006) and Poor and Smith (2004) estimate MCS
at 21 € (34.87AUD) and 13 € (19.26USD) per visitor16 to a special event in Queensland
(Australia) and a cultural heritage site in Maryland (USA) respectively. Using ITCM, Paru­
mog, Cal and Mizokami (2003) or Alberini and Longo (2006) calculate this value at 4 €
(260.19PHP) per visitor to two cultural heritage sites in Cebu (Philippines) or 32.37 €
(18,440AMD) per visitor to four cultural heritages in Armenia respectively. These differ­
ences might reflect the tremendous cultural and social value that citizens attach nowadays to
blockbusters exhibitions.
Comparison of the sensitivity of the estimated demand function to price throws up con­
tradictory results. Poor and Smith (2004), obtain a practically identical demand function of
unitary elasticity (–1.074) to that obtained in this study. Parumog et al. (2003) however, es­
timate a highly price-elastic demand function with an average value for both sites of
–6.896. Both studies consider culture as an inferior good, obtaining negative income elas­
ticities (–0.749 and –6.393) in both instances. This differs substantially from our findings
in particular and generally from literature on the topic, in which the different types of cul­
tural activities usually have positive and in many cases high elasticities. We believe that our
findings are more in line with reality. It is more normal for cultural products to be luxuries
rather than inferior goods, given that they are more widely consumed in more highly devel­
56
EVA VICENTE AND PABLO DE FRUTOS
oped countries. Societies usually begin to concern themselves with culture and cultural her­
itage preservation once other basic needs have been dealt with (Greffe, 1990: 63). The elas­
ticity of these types of goods would be more similar to items consumed when the income
per capita starts to increase, for example all consumer goods and services related to leisure
and recreation.
The results of our work evidence that TCM is a suitable technique for estimating con­
sumer surplus derived from blockbuster arts exhibitions. The findings to emerge from our
work specifically highlight the important social benefits linked to staging special exhibi­
tions. We believe that this method can be used to value other types of temporary activities
and cultural events capable of attracting a significant number of visitors to where they are
held and in which the use value or benefits are significant. As with other non-market valua­
tion methods, TCM displays huge potential as a tool for cultural planning. Actually, in re­
cent years the economic valuation of cultural goods and services has gained in relevance
within cultural policy. Applying this approach provides valuable information for cultural
managers and policy-makers. Firstly, it provides an estimation of the demand for cultural
goods and their elasticities. This information will enable prediction of future trends and may
contribute towards designing successful pricing strategies for cultural activities. The con­
sumer surplus calculation allows the comparison of the social benefits derived from this type
of activity with its costs, which may help to assign public resources in a more rational man­
ner. The satisfaction derived by consumers or visitors to cultural activities can also be esti­
mated and used to compare different cultural institutions and projects in terms of their abil­
ity to satisfy the wants and preferences of the general public.
Our study clearly has its limitations and leaves the way open for future research oppor­
tunities. As highlighted throughout our work, despite its enormous potential for valuing cul­
tural goods, TCM also evidences certain limitations. TCM only reflects visitor use values to
emerge from the supply of cultural goods, excluding non-use values which, on occasions,
might prove significant. In this sense, the method underestimates demand and therefore, the
social benefits linked to the supply of cultural goods. Although estimating the use value of
blockbuster exhibitions in itself can provide valuable information, in order to gain a deeper
insight into the social benefits to emerge from the provision of such cultural goods addition­
al non-market techniques could be employed, amongst which the contingent valuation
method is the most logical choice. One area of future research into the valuation of the so­
cial benefits provided by blockbuster exhibitions would thus be to conduct a contingent val­
uation study. It should also be pointed out that estimating the total economic value of this
kind of exhibition also involves taking account of the positive externalities to emerge from
hosting such cultural projects for society as a whole. One of the most important is the major
indirect economic benefit for the regional and/or local economy that such events can gener­
ate given their enormous tourist appeal. A further interesting area of future research would
be to explore the economic impact of this kind of exhibition. Jointly with the application of
non-market techniques, this approach would provide more comprehensive information con­
cerning the economic and social benefits linked to the staging of this kind of cultural proj­
ect.
Application of the travel cost method to estimate the economic value of cultural goods
57
Notes
1.­ Please refer to compilations from Noonan (2002) or Snowball (2008), among others.
2.­ This technique has been applied recently to measure the benefits of a special event, the Gemfest in Queens­
land (Australia) (Prayaga, Rolfe and Sinden, 2006), although since it concerns a jewellery fair it does not ac­
tually relate to the subject of the study we are attempting to measure here.
3.­ The singularity of the pieces exhibited (which are on occasion private property) together with no opportunity
to view the items again either separately or together are strong incentives for the public to visit these events
in order not to miss out. The time restriction increases visitor incentives by creating a sensation of urgency
(Frey, 2000). These behaviours are not observed in other types of permanent exhibitions or cultural activities,
in which the decision to postpone the visit is easier as it is felt that nothing is thereby lost.
4.­ The more welcoming nature of temporary exhibitions helps to break down social and psychological barriers
which hold people back from accessing art if they are unfamiliar with the art culture, allowing them to over­
come the reticence that visiting museums may cause (Frey, 2000). This phenomenon is especially true for
events that take place in public spaces, which are more accessible to the general public and less intimidating
than traditional centres and cultural institutions.
5.­ Although on occasions this kind of activity may lead to excess demand and therefore the possible risk of over­
crowding, the likelihood of exclusion avoids such situations. In general, regardless of whether or not an entrance fee is charged, visitor admission to events of this nature is based on their carrying capacity, calculated
due to the quality of the experience and visitor comfort (García, 2001), among other aspects. This restriction
on visitor number may give rise to queues at the entrance to the exhibition, yet it ensures the quality of the ex­
perience for all the visitors and maintains the non-rival consumer nature of this kind of service. As a result,
the extent to which these goods are rival or non-rival will in each case depend on the conditions and levels of
service in which this kind of cultural product is provided.
6.­ It should be pointed out that providing free admission to this kind of exhibition is a common practice among
many institutions, and is based on a wish to disseminate culture. The decision whether or not to charge admis­
sion to the exhibition will in any case depend on the profile of the organisers, their social function and the need
or otherwise to recover the expected outlay.
7.­ In these instances the demand for the cultural goods would be underestimated as they would not include non­
users omitting non-use values which, in many cases, would be significant (Ready and Navrud, 2002; Ben­
hamou, 2003). Therefore, the use of this method would be limited to valuation of sites entailing significant
travel (Mourato and Mazzanti, 2002), as in this study.
8.­ This situation is quite common in the area of cultural goods and services where multiple individual visits are
infrequent, and is why most studies valuing such goods and services conducted to date have also employed
ZTCM (see Martin, 1994; Poor and Smith, 2004 or Forrest et al., 2000).
9.­ The TCM is based on the assumption that the travel cost to enjoy an event or cultural attraction is a satisfac­
tory proxy of the visitor’s willingness to pay (Throsby, 2001; Benhamou, 2003). This situation arises when
two conditions are met: that such an event or attraction is the sole purpose of the journey and that the journey
does not involve any other type of enjoyment by itself. This means that the method may only be applied to
value goods which fulfil these essential assumptions to a sufficient degree (Frey, 2000). In practice, to ensure
these hypotheses are complied with, many researchers work with truncated samples, choosing only those vis­
itors who state that the visit to the site or event is the basic reason or purpose for their trip. This procedure is
common in other studies addressing valuation of cultural goods and special events such as the works of Poor
and Smith (2004) and Prayaga, Rolfe and Sinden (2006).
10.­ The Hicksian compensating variation and equivalent variation welfare measures are the theoretically correct
measures of the value of the benefits, even though Willig (1976) showed that consumer surplus is an accept­
able approximation.
11.­ TCM was originally developed to value natural spaces where no residents lived, as a result of which all the
visitors incurred access costs. The two other possible alternatives would have involved, firstly, allocating the
58
EVA VICENTE AND PABLO DE FRUTOS
mean cost of the sample unit (province) to which the town belongs, which would not have proved accurate and
would have led to overestimations of the surplus. The second option would have been to allocate a zero trav­
el cost, which is not possible either in the provincial model used, where i corresponds to a territorial body
which is determined administratively. This would have fractured the homogeneity in the disaggregation. As a
result it was decided to remove the residents.
12.­ In most cases, visitors who travelled by coach formed part of organised trips subsidised in part or in full, mean­
ing that it was either impossible to calculate the true access cost or it was extremely difficult to distinguish
what part of the cost of the trip corresponded to each of the items making up the total cost (petrol, meals, etc.)
since the price paid by the visitor might include these or might not. Due to the “noise” which such visitors
brought into the models it was decided to remove them, a practice also used by other authors such as Saz and
Pérez y Pérez (1999).
13.­ It is expected that this proportion is particularly reduced for blockbuster exhibitions given the close relation­
ship with tourism. Evidence of this is the high percentage of visitors to these events who come from outside
the city, from another region, and even from abroad.
14.­ Although findings from empirical studies carried out to date differ, they generally tend to support the hypoth­
esis of low price elasticity of the demand for cultural goods and services (Albi, 2003; Prieto and Fernández,
2006). Nevertheless, the majority of these studies estimate the elasticity-price of the demand for the whole of
a cultural subsector, and therefore the results would vary greatly for institutions or specific cases in which
greater values would be obtained and occasionally values greater than minus one (Heilbrun and Gray, 1993;
Albi, 2003; Seaman, 2006).
15.­ In fact, if we analyse museum entrance fees, we see how those applied to special exhibitions are usually high­
er than for permanent exhibitions, and indeed many museums which do not normally charge entrance fees
begin to do so for temporary exhibitions.
16.­ Conversion to euros has been calculated based on the official rate of exchange in October 2009. These values
reflect the year in which the study was carried out and have not been updated.
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Resumen
En los últimos años un número creciente de trabajos han aplicado técnicas de valoración de no merca­
do para estimar el valor económico de los bienes culturales. La mayoría utilizan técnicas de preferen­
cias declaradas, como el método de valoración contingente. En este trabajo se aplica el método del
coste del viaje para estimar el valor económico de un tipo concreto de bienes culturales: las exposicio­
nes especiales. El trabajo empírico se centra en el caso específico del ciclo expositivo “Las Edades del
Hombre”, uno de los primeros y más representativos ejemplos de exposición blockbuster en España.
Esta es la primera vez que este método se utiliza para valorar una gran exposición temporal y una de
sus escasas aplicaciones en la valoración de bienes culturales.
Palabras clave: exposiciones temporales blockbuster, técnicas de valoración de no mercado, preferen­
cias reveladas, método del coste del viaje, economía de la cultura.
Clasificación JEL: H41, D60, Z11
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