A set of therapists are interested in testing whether spending time with a pet while a patient is hospitalized can reduce anxiety symptoms. They have some pre-existing knowledge to suggest that pet therapy is helpful, but they want to know whether the size of the pet matters. Below is a subset of their data:

Small Dog	Medium Dog	Large Dog
6	3	4
5	2	3
4	4	5
7	5	1
8	1	1

• What is the independent variable? (1 point)
• What are the levels of the independent variable? (1.5 points)
• Conduct all five steps of a one-way analysis of variance to determine if there is a difference in stress based on animal size. (12 points total)
  • STEP 1: STATE THE HYPOTHESES
  • Null hypothesis in written and statistical notation form (1 point)
  • Alternative hypothesis in written and statistical notation form (1 point)
  • STEP 2: DETERMINE THE SAMPLING DISTRIBUTION
  • There are three samples from separate populations and there is a single score for each case within each sample. We need to analyze the variance of the samples and therefore will use the F distribution and the ANOVA test (0 points)
  • STEP 3: SET P VALUE AND DETERMINE CRITICAL VALUES
  • Correct degrees of freedom between and within (1 point total)
  • Correct critical value (1 point)
  • STEP 4: CONDUCT HYPOTHESIS TEST AND COMPARE TO CRITICAL VALUE
  • Correct equation used (1 point)
  • Correct within-groups variance found (1 point)
  • Correct between-groups variance found (1 point)
  • Correct F statistic value found (1 point)
  • Demonstrates comparison of F obtained to F critical (1 point)
  • STEP 5: DECISION AND CONCLUSION
  • Decision: Fail to Reject or Reject the null hypothesis (1 point)
  • Conclusion: Written in words a clear interpretation of results (1 point)
  • Writes conclusion in statistical notation (1 point)
• Based on the results above, make a recommendation to a hypothetical therapist about pet therapy and patient stress.
  • Write 1-2 sentences demonstrating understanding of F statistic and what a significant or non-significant result means. This may require discussion of future analyses (2.5 points).