Imagine you are hired by the California Avocado Commission to investigate how in-store advertising of Avocados affects organic avocado sales. The Avocado Commission partneredwith stores in Beverley Hills to advertise organic avocados in their produce section. They wantyou to run a regression of avocado sales on the amount of money spent on in-store advertising. Based on the results of the study, the are going to decide whether to expand this add campaignto the rest of the state. (a) Does this seem like a representative sample to you? Why or why not? If not, what can you say with this data?
(b) Imagine the commission makes any changes to the data set you give above. Now do you think you're results will be causal? What may be some other variables you want to control for?
(c) Pretend you cannot get any of the variables you list above. Lets try to sign the bias. Choose any one of the variables you list. Draw a Venn diagram like we did in class. Try to figure out what sign the bias will be
(d) The Avocado Commission is worried about controlling for the distance from a store to the nearest farmer's market. They want you to include the distance to the nearest farmer's market. One person on The Commission points out that there are a lot of families who visit California from other countries. He suggests including both the distance to the nearest farmer's market in miles and in kilometers because the people from outside of the U. S. will think of the distance in kilometers. Do you think this is a good idea? Why or why not? Explain any technicalities that help support your answer.