Marketing - MaxDiff - Save Variable(s) - Proportion of Correct Predictions

Create a new variable which contains the proportion of correct predictions for each respondent, according to a MaxDiff latent class analysisMaxDiff latent class analysis, MaxDiff hierarchical BayesMaxDiff hierarchical Bayes or MaxDiff ensembleMaxDiff ensemble output. You should select the output before running this script.

Example

The script produces a SUMMARY table with the new variable:

Technical details

Prediction accuracy is measured in terms of the proportion of a respondent's questions in which the best alternative was correctly predicted. If cross-validation is used, the predictions are made on only the holdout (out-of-sample) questions. Otherwise, predictions are made on all of the respondents' questions.

How to apply this QScript

Start typing the name of the QScript into the Search features and data box in the top right of the Q window.
Click on the QScript when it appears in the QScripts and Rules section of the search results.

OR

Select Automate > Browse Online Library.
Select this QScript from the list.

Customizing the QScript

This QScript is written in JavaScript and can be customized by copying and modifying the JavaScript.

Customizing QScripts in Q4.11 and more recent versions

Start typing the name of the QScript into the Search features and data box in the top right of the Q window.
Hover your mouse over the QScript when it appears in the QScripts and Rules section of the search results.
Press Edit a Copy (bottom-left corner of the preview).
Modify the JavaScript (see QScripts for more detail on this).
Either:
- Run the QScript, by pressing the blue triangle button.
- Save the QScript and run it at a later time, using Automate > Run QScript (Macro) from File.

Customizing QScripts in older versions

Copy the JavaScript shown on this page.
Create a new text file, giving it a file extension of .QScript. See here for more information about how to do this.
Modify the JavaScript (see QScripts for more detail on this).
Run the file using Automate > Run QScript (Macro) from File.

JavaScript

includeWeb('QScript R Output Functions');

saveVariables('Proportion correct', 'MaxDiff',
              'input.maxdiff = ',
              '\ninput.maxdiff$prediction.accuracies\n', null, null, 'prop.corr', ['FitMaxDiff', 'MaxDiffEnsemble']);