Now that you know a little bit more about what this study involves ... how would you go about addressing this study? What would be your first steps to make some sense of this data and answer the question - what is the optimal fat content level for ice cream?
Dr. Harkness walks through some early steps that you might consider...
The data for the of the study is summarized below as an 8 × 9 two-way table:
You could do an ordinary Chi-square test...
...and here is a copy of the Pearson's ChiSquare test results:
***** ANALYSIS OF OBSERVED FREQUENCY TABLE 1
MINIMUM ESTIMATED EXPECTED VALUE IS 1.33
Conclusion this point...
Clearly, we should not be satisfied with just simply demonstrating that there is a significant difference in the different ice creams with varying fat levels. Don't we want to 'model' the ratings as a function of the fat levels? Won't this be a better way to understand which fat level is optimal? How will Polytomous Logistic Regression help provide us with a more helpful analysis?