Untitled

principal components analysis
Principal component analysis is a multivariate
statistical technique designed to order and simplify
the relationships between a large set of variables.
Therefore, it is considered to be a data reduction
technique. It is most often described as a type of
factor analysis, but sometimes is presented as an
alternative to it. This technique takes the correlations
between a large number of variables and uses
these to derive a smaller set of factors. Factors
represent hypothesised underlying variables which
explain the responses given to a set of the variables
measured. It is a technique particularly suited to
the investigation of underlying patterns in data
such as large numbers of attitude statements or
rating scales.
All factor analyses share the same basic steps.
First, a correlation matrix is produced for all the
variables under investigation. These correlations
are then examined in order to extract factors which
explain the variance in one or more of the
variables being analysed. These resulting factors
are then usually rotated to produce the clearest
possible interpretation of the factors.
Principal components analysis is a particular
method for extracting factors, a common technique
used in tourism to study, for example, vacation
motivation, destination choice or host attitude.
Principal components are always orthogonal, that
is, independent of each other, and the first factor
always explains the largest amount of the variance;
the second factor explains the next largest amount
of the variance, and so on. Principal components
are usually contrasted with common factors, which
are the other main extraction method used in
factor analysis. Principal components are derived
from the data, whereas common factors reflect
causal relationships which the researcher has
hypothesised to exist between the variables. This
distinction means that this analysis technique is
strictly a data reduction and exploration technique.
Further reading
Lui, J.C., Sheldon, P.J. and Var, T. �1987) `Resident
perception of the environmental impacts of
tourism' Annals of Tourism Research 14�1): 17±37.
�Offers an example of the use of principal
components factor analysis in an investigation
of resident attitudes towards tourism.)
Moscardo, G., Morrison, A.M., Pearce, P.L., Lang,
C. and O'Leary, J.T. �1996) `Understanding
vacation destination choice through travel motivation
and activities', Journal of Vacation Marketing
2�2): 109±22. �Provides an example of the use
of principal components factor analysis in an
investigation of tourism motivation.)
Stevens, J. �1986) Applied Multivariate Statistics for the
Social Sciences, Hillsdale, NJ: Lawrence Erlbaum
and Associates. �The chapter on principal
components which discusses this technique is
relatively free of mathematical equations.)
product
product 461
GIANNA MOSCARDO, AUSTRALIA
The concept of a tourism product is, at first glance,
deceptively simple. A tourism product presumably
is whatever one buys while away from home.
Indeed, from a marketing perspective, one can
define any product as `anything that can be offered
to a market for attention, acquisition, use or
consumption that might satisfy a need or want. It
includes physical objects, services, persons, places,
organisations, and ideas' �Kotler 1984: 463). In the
context of tourism, the most common types of
products arguably are services and places, although
tourists will also use physical objects, persons,
organisations and ideas.
Marketers, however, tend to view tourism
products ± and services in general ± as being fairly
complex phenomena. Some authors suggest tourism
products consist of a number of components or
layers. One model suggests that tourism products
consist of two parts: a `tangible' good or service,
and its symbolic value. Another model suggests
there is a core component �such as an airline
flight) and peripheral components �such as reservations
and baggage handling). A slightly more
complex model posits three levels: a `formal'
commodity the customer is seeking �usually conceived
as specific benefit the visitor is seeking, such
as a relaxing weekend), a `core' commodity actually
being sold �such as a room at a resort and access
to a golf course), and an enhanced commodity that