This tutorial will help you design and interpret a MaxDiff (Best/Worst) analysis in Excel using the XLSTAT statistical software.
What is MaxDiff analysis?
MaxDiff analysis is a marketing method allowing the user to know the consumer's expectations about a product and to model the importance of the attributes related to the product. The MaxDiff analysis method is now common in marketing. The modeling of consumer choice is a key area of marketing. MaxDiff analysis is used to understand the key attributes of a products, and is less complicated than conjoint analysis while still giving interesting results.
If you want to simulate markets, you should prefer conjoint analysis.
XLSTAT-Conjoint is a statistical program which allows you to run through all the analytical steps of MaxDiff analysis which can be divided in four steps:
- Choice of the relevant attributes to describe the products.
- Generation of design of experiments based on incomplete block designs.
- Collection of the results in Microsoft Excel sheets.
- Data analysis with a specific method: hierarchical bayes.
In this tutorial, we will detail the steps necessary for the implementation and interpretation of a MaxDiff analysis with XLSTAT.
Dataset to conduct a MaxDiff analysisIn this tutorial we will look at a simple simulated case of MaxDiff analysis based on tourism marketing.
A hotel brand wishes to open a new hotel and would like to understand the importance of attributes of a vacation destination in order to define its offer.
An Excel spreadsheet containing the results of this example can be downloaded by clicking here. The results are divided into different sheets:
- Attributes: This sheet contains the attributes selected to describe the products.
- Designs for MaxDiff: This sheet contains the generated design, and the choices given by 5 respondents.
- MaxDiff: This sheet contains the results of MaxDiff analysis by hierarchical Bayes
Step 1: Choosing the attributesThe first step in this MaxDiff analysis is done in collaboration with experts in the tourism market. We focus on choosing the important attributes to define a touristic destination. The selected attributes are:
- Quality beaches
- Cultural activities
- Luxury hotel offer
- Shopping around
- Wildlife close by
- Local cuisine
Step 2: Generation of the comparisons
XLSTAT allows you to create sets of attributes to be compared by the respondents. A design of experiments method is used.
Once XLSTAT is started, click on the CJT icon and choose the Designs for MaxDiff analysis feature.
Once the button is clicked, the dialog box appears.
You can then enter the name of the analysis, select the attributes names, enter the number of comparisons (8) and the number of profiles per comparison which corresponds to the size of each set of attributes (4). These values have to be chosen by the user so that the dataset that will be collected is big enough to obtain significant results, while not being too long to let the respondents stay focused throughout the questionnaire.
In the Outputs tab, we choose the Combination / Respondent format, which means combinations will be in rows while responses of respondents will be in columns. We do not activate the Print individual sheets option, as they are not necessary in this example. In a comprehensive analysis, they can be very useful in order to get the results directly filled in by the respondents in individual Excel worksheets.
Once you click the OK button, the computations are run, then the results are displayed.
The main table is the table of choice, found in the MaxDiff sheet and must be completed after the individuals (respondents) have been interviewed. Choices are between 1 and 4 for each individual. There are two columns per individual, one for the most important attribute (best) and one for the least important attribute (worst).
Step 3: Fill in the MaxDiff analysis table
The MaxDiff analysis tables can either be filled in directly after interviewing individuals about their choices externally, or directly using the individual sheets and automatic referencing of results. This is especially interesting in the context of MaxDiff analysis because completing the overall table can be complex.
In our case, individual 1 thinks Entertainment is the most important attribute and having wildlife around is the least important within the 4 presented attributes in the first set or combination (C1).
Step 4: Results of the analysis
As part of this analysis, 5 individuals have been asked about their preferences in terms of touristic destination. The results are available in the MaxDiff sheet.
Once the MaxDiff design is filled with the responses, you are ready to run the analysis. One option is to click on the button Run the analysis which automatically launches the interface with the loaded data.
Alternatively, you can click on the CJT icon and choose the MaxDiff feature.
You can then select the data.
To facilitate data selection and avoid to manually select the two required datasets (Responses and Combinations), you can click on the magic stick. This will automatically load the two datasets if the MaxDiff design has been generated with XLSTAT and if you did not manually modify the worksheet containing the design. A new window will pop up. Select any cell of the worksheet containing the MaxDiff design generated with XLSTAT. In this example, we selected the H13 cell of the Design for MaxDiff sheet. Then click on OK.
You can also select your data manually. In the Responses field, select the 10 columns of the table of responses provided by the respondents. In the table of choices, select the four columns of the attributes.
In the options tab, we select the Hierarchical Bayes method and we leave all the other values as default.
Once you click the OK button, the computations are performed and the results are displayed.
The MaxDiff scores are displayed as rescaled coefficients summing up to 100. We see that Individual 1 thinks nightlife and entertainment are very important. Shopping around and wildlife are also important but to a lesser extent.
Then the descriptive statistics are shown. If we check the Means column, we see that nightlife, cultural activities and luxury are the most important attributes on average.
We can visualize average MaxDiff scores on the chart below.
After this preliminary study, we would advise the hotel chain to focus on nightlife in a luxury hotel with cultural activities.