Imagine a researcher wanted to assess people€™s fear of dogs as a function of the size of the dog. He assessed fear among people who indicated they were afraid of dogs, using a 30-point scale from 0 (no fear) to 30 (extreme fear). The researcher exposed each participant to three different dogs, a small dog weighing 20 pounds, a medium-sized dog weighing 55 pounds, and a large dog weighing 110 pounds, and assessed the fear level after each exposure. Here are some hypothetical data; note that these are the data from Exercise 11.39, on which you have already calculated numerous statistics:

a. State the null and research hypotheses.

b. Determine whether the assumptions of random selection and order effects were met.

c. In Exercise 11.39, you calculated the effect size for these data. What does this statistic tell us about the effect of size of dog on fear levels?

d. In Exercise 11.39, you calculated a Tukey HSD test for these data. What can you conclude about the effect of size of dog on fear levels based on this statistic? 

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Person 1 2 3 4 7 16 Small dog Medium dog 15 18 18 13 Large dog 22 28 26 29 3.