Question

1. (

1. (6 pts) What are the null and alternative hypotheses? (There will be three of each.)
2. (8 pts) Copy out the entire ANOVA table from JASP, SPSS, or the online calculator. Say what the results mean in terms of rejecting or retaining each null hypothesis (alpha = .05). For each F test, report F_crit as well.
3. (6 pts) Graph the results. Include one point on the graph for each cell mean (4 data points total). Also report each cell mean numerically in a Table. Follow the book’s graphing conventions (see Question 3, above).
4. (4 pts) Explain in a few sentences and annotation of the graph how the numerical analysis and graph each show evidence for any main effects of the two independent variables and/or for an interaction between the two independent variables (whichever are reliable in this analysis). In other words, for which group or groups does the drug appear to be effective?

   time	prevuse	concentration
   51	1	1
   48	1	1
   62	1	1
   71	1	1
   53	1	1
   61	1	1
   55	1	1
   64	1	1
   27	1	2
   30	1	2
   37	1	2
   47	1	2
   40	1	2
   29	1	2
   31	1	2
   35	1	2
   48	2	1
   55	2	1
   55	2	1
   61	2	1
   69	2	1
   64	2	1
   59	2	1
   59	2	1
   52	2	2
   60	2	2
   58	2	2
   64	2	2
   49	2	2
   60	2	2
   53	2	2
   55	2	2

   
   

Answer 1

• (6 pts) What are the null and alternative hypotheses? (There will be three of each.)

The hypothesis being tested is:

H0: There is no main effect of prevuse

Ha: There is a main effect of prevuse

The hypothesis being tested is:

H0: There is no main effect of concentration

Ha: There is a main effect of concentration

The hypothesis being tested is:

H0: There is no interaction effect

Ha: There is an interaction effect

• (8 pts) Copy out the entire ANOVA table from JASP, SPSS, or the online calculator. Say what the results mean in terms of rejecting or retaining each null hypothesis (alpha = .05). For each F test, report Fcrit as well.

Analysis of Variance

Source	DF	Adj SS	Adj MS	F-Value	P-Value
prevuse	1	1012.5	1012.50	24.02	0.000
concentration	1	1352.0	1352.00	32.07	0.000
prevuse*concentration	1	903.1	903.12	21.43	0.000
Error	28	1180.3	42.15
Total	31	4447.9

Reject all the hypotheses.

• (6 pts) Graph the results. Include one point on the graph for each cell mean (4 data points total). Also report each cell mean numerically in a Table. Follow the book’s graphing conventions (see Question 3, above).

• (4 pts) Explain in a few sentences and annotation of the graph how the numerical analysis and graph each show evidence for any main effects of the two independent variables and/or for an interaction between the two independent variables (whichever are reliable in this analysis). In other words, for which group or groups does the drug appear to be effective?

There is a main effect of concentration and prevuse.

There is an interaction effect.