Study questions

6. Change LOCATION from a factor to a variable and rerun the regression analysis. Are there any differences in the results? Explain why. Rewrite the algebraic expression for the model given in the case study with the term representing LOCATION now taking on the form of a covariate. Plot a scatter plot of milk offtake versus location and explain why the regression coefficient, which is equivalent to the slope of the line between the mid points for the two locations, is equivalent to the mean difference in offtakes.
7. What other factors or traits do you consider might have important effects on milk offtake? Write down a suitable statistical model that incorporates these factors. What implications do any of these factors have in study design?
8. Prepare a protocol for estimating average milk offtake and average human consumption in a group of smallholder farms possessing in the range of 1-4 cows. Explain how you would record the data and what approach you would use to analyse the data. Discuss any limitations of such a study.
9. In light of the results obtained in this Case Study redesign the part of the questionnaire given in CS1Quest1 so that it better achieves the objectives set and allows simpler and direct computer entry. Sketch out a simple computer screen to show how the data might be entered.
10. One of the proposals resulting from the participatory study was to conduct another participatory study to quantify drug use. Using similar methods as described in the paper plan how you would find out which types of animals the farmers would select for prophylactic treatment and at what dose.