Perceptual mapping has been used extensively in marketing. This powerful technique is used in new product design, advertising, retail location, and many other marketing applications where the manager wants to know
1. The basic cognitive dimensions consumers use to evaluate "products" in the category being investigated; and
2. The relative "positions" of present and potential products with respect to those dimensions.
When used correctly perceptual mapping can identify opportunities, enhance creativity, and direct marketing strategy to the areas of investigation most likely to appeal to consumers.
Perceptual mapping has received much attention in the literature. Though varied in scope and application, this attention has been focused on refinements of the techniques, comparison of alternative ways to use the techniques, or application of the techniques to marketing problems.' Few direct comparisons have been made of the three major techniques—similarity scaling, factor analysis, and discriminant analysis. In fact, most of the interest has been in similarity scaling because of the assumption that similarity measures are more accurate measures of perception than direct attribute ratings despite the fact that similarity techniques are more difficult and more expensive to use than factor or discriminant analyses.
In practice, a market researcher has neither the time nor the money to simultaneously apply all three techniques. He/she usually selects one method and uses it to address a particular marketing problem. The market researcher must decide whether the added insight from similarity scaling is worth the added expense in data collection and analysis. Furthermore, if the market researcher selects an attribute-based method such as factor analysis or discriminant analysis he/she wants to know which method is better for perceptual mapping and how such maps compare with those from similarity scaling. To answer these questions, one must compare the alternative mapping techniques.
One way to compare these techniques is theoretically. Each technique has theoretical strengths and weaknesses and the choice of technique depends on how consumers actually react to the alternative measurement tasks.
Another comparison approach is Monte Carlo simulation. This useful investigative tool has been employed by researchers to explore variations in similarity scaling and other techniques.
In perceptual mapping Monte Carlo simulation can compare the ability of various techniques to reproduce a hypothesized perceptual map, but it requires that the researcher assume a basic cognitive structure of the individual. Monte Carlo simulation leaves unanswered the empirical question of whether the analytic technique can adequately describe and predict an actual consumer's cognitive structure.
The comparison procedure we use is practical and is based on theoretical arguments and empirical analyses to identify which procedures yield results most useful for marketing research decisions. If the theoretical arguments are supported, researchers can continue to subject a technique to empirical tests in alternative product categories. In this way, one gains insight about the techniques by learning their strengths and weaknesses. If and when the hypotheses are falsified new theories will emerge.
We chose the following guidelines for the comparison.
1. The marketing research environment should be representative of the way the techniques are used empirically.
2. The sample size and data collection should be large enough to avoid exploiting random occurrences and should have no relative bias in favor of the techniques identified as superior.
3. The use of the techniques should parallel as closely as possible the recommended and common usage.
4. The criteria of evaluation should have managerial and research relevance. To fulfill these criteria, we chose an estimation sample and a saved data sample of 500 consumers each, drawn from residents of Chicago's northern suburbs. The application area is perceptions of the attractiveness of shopping areas in the northern suburbs and the criteria are the ability to predict consumer preference and choice, interpretability of the solutions, and ease of use.
Comparison of Similarity Scaling and Attribute-Based Techniques
A major difference between similarity scaling and the attribute-based techniques is the consumer task from which the perceptual measures are derived. Attribute ratings are more direct measures of perceptions than similarity judgments, but may be incomplete if the set of ratings is not carefully developed. Similarity judgments introduce an intermediate construct (similarity) but the judgments are made with respect to the actual product rather than specific attribute scales. A priori, if the set of attributes is relatively complete there is no theoretical reason to favor one measure over the other.
Another difference is the treatment of variation among consumers. In the attribute-based techniques a common structure is assumed, but the values of individual measures are not restricted. In similarity scaling it is restricted to be at most a stretching of the common measure.
Finally, similarity scaling is limited by the number of products. At least seven or eight are needed for maps in two or three dimensions (Klahr 1969). There are no such restrictions for factor analysis. The restriction for discriminant analysis is the number of products minus one. This argument favors attribute-based techniques if the number of products in a consumer's evoked set is small; it favors neither technique if the number of products is large. In practice, the evoked set averages about three products (Silk and Urban 1978).
On the basis of these arguments, if the attribute set is reasonably complete, attribute-based techniques should provide better measures of consumer perception than similarity scaling.
Comparison of Factor Analysis and Discriminant Analysis
Factor analysis is based on the correlations across consumers and products. Discriminant analysis is limited to dimensions that, on average, distinguish among products. Thus factor analysis should use more attributes than discriminant analysis in the dimensions and therefore produce richer solutions. For example, consider Mercedes Benz and Rolls Royce. Suppose that the true perceptual dimensions are country of origin and reliability and that only reliability affects preference and choice. Suppose that perceptions of country of origin differ among products. Suppose that average perceptions of reliability are the same for both cars but individual perceptions differ among consumers. Discriminant analysis will identify only country of origin. Factor analysis will identify both dimensions.
On the basis of this type of argument, one expects factor analysis to provide a richer perceptual structure than discriminant analysis. It should be able to use more of the attribute ratings and should identify perceptual dimensions that predict preference and choice better than discriminant analysis dimensions.
IMPLICATIONS AND FUTURE RESEARCH
Perceptual mapping is an important marketing research tool used in new product planning, advertising development, product positioning, and many other areas of marketing. Strategies based on perceptual maps have led to increased profits, better market control, and more stable growth. Furthermore, much research is based on implications of market structure as identified by perceptual maps. Because of this interest and use, it is crucial that the best mapping technique available be employed in these applications.
Factor analysis is likely to be superior in categories where:
1. The number of products in the average consumer's evoked set is relatively small (seven stimuli or less).
2. There is variation in the way consumers perceive products in the category.
3. Qualitative research has identified a set of attributes likely to represent the product category.
The presence or absence of these characteristics does not ensure the superiority of one technique, but without evidence to the contrary they can serve as guidelines.
Source: “Alternative Perceptual Mapping Techniques: Relative Accuracy and Usefulness“ By JOHN R. HAUSER and FRANK S. KOPPELMAN *
Submitted By:
Yoshita Malkotia
MBA-Finance
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