To ensure that your results are valid, consider the following guidelines when you collect data, perform the analysis, and interpret your results.
- The data must include at least 3 components
- To define a mixture experiment in Minitab, you must have at least two components that are continuous. If you do not have at least two components, you don't have a mixture. However, you must have at least three components to display on a simplex design plot.
- Ensure that the measurement system produces reliable response data
If the variability in your measurement system is too great, your experiment may lack the power to find important effects.
- Each observation should be independent from all other observations
If your individual observations are dependent, your results might not be valid. Consider the following points to determine whether your observations are independent:
- If an observation provides no information about the value of another observation, the observations are independent.
- If an observation provides information about another observation, the observations are dependent.
- The experimental runs should be randomized
Randomization reduces the chance that uncontrolled conditions will bias the results. Randomization also lets you estimate the inherent variation in materials and conditions so that you can make valid statistical inferences based on the data from your experiment.