1) Researchers have found that providing therapy dogs on collegecampuses near midterms and finals is an effective way to reducestudent stress. They wondered if providing other animals would alsoreduce stress. To find out, they brought four different animals tocampus and had students rate their stress level after time spentwith the animal. The results are presented below.
OBSERVED | | Dog | Cat | Ferret | Lizard |
More Stressed | 18 | 32 | 38 | 92 |
Same Stressed | 30 | 28 | 42 | 40 |
Less Stressed | 132 | 90 | 40 | 18 |
a) Specify the null and alternative hypotheses for a chi-squaretest of independence
B)Fill in the table below with the expected frequencies
EXPECTED | | Dog | Cat | Ferret | Lizard |
More Stressed | | | | |
Same Stressed | | | | |
Less Stressed | | | | |
c) Use the observed and expected frequencies to calculate achi-square test of independence to detect any relationship betweentype of animal and feelings of stress, using alpha = .01. Reportthe critical value and your decision.
e) Calculate the effect size for the relationship between animaltype and stress level.
