To ensure that your results are valid, consider the following guidelines when you collect data, perform the analysis, and interpret your results.

- The response should be numeric
- To calculate the mean response at different factor levels, the multi-vari chart requires numeric response data.
- Each factor should have at least 2 levels
- You may have up to four numeric, text, or date/time factors. Each factor must have at least 2 levels.
- You must have observations for enough factor level combinations
- You need observations for at least 60% of all possible factor level combinations for Minitab to create the chart.