Question

1. a. We know that some people people who are highly suggestible have a vivid imagination and fantasy life. This leads us to hypothesize that the ability to recall dreams ill also be affected by hypnotic susceptibility (HS). Using the Stanford Scale of Hypnotic Susceptibility, we create low, medium, and high susceptibility groups by selecting from volunteers who took the scale. We then asked the volunteers to keep a dream diary for 1 month. At the end of the month, we collect the diaries and count the number of dreams recalled for each person: Low HS are more susceptible to hypnosis than others and that Medium HS High HS 22 4 14 9 12 26 3 13 8 26 20 14 15 27 16 19 19 8 17 16 5 on dream recall using alpha .05 and complete all 6 steps. 10 14 Compare the groups 1b. The means for the low HS (M = 9.375), medium HS (M 13.875), and high HS (M= 19.625) can be used to determine post-hoc comparisons using HSD7.2270. Complete the different table and include which groups are different from one another in the putting it all together conclusion. 1c. How big is the effect? Id. Interpret the effect. C

Answer 1

(a) here the null hypothesis H0: mu_low=mu_medium=mu_high

alternate hypothesis Ha: atleast one mu is different from others

the p-value=0.0064 of the between groups is less than typical level of significance alpha=0.05, so we reject the null hypothesis H0

( or equivalently the observed F=6.48 is more than critical F=3.47, so we reject H0)

(b) if the difference is more than HSD, then that comparison will be significant and it is found that Low HS is different than High HS.

comparison		difference	HSD	Remarks
Low	Medium	4.5	7.227	Non-significant
Low	High	10.25	7.227	Significant
Medium	High	5.75	7.227	Non-significant

(c) effect size=between group SS/ Total SS=422.33/684.625=0.6169

(d)   larger values eta-squared leads the significant differences among the treatments

giving 0.01 (small), 0.09 (medium) and 0.25 (large)

following one way anova information has been generated using ms-excel

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
Low	8	75	9.375	15.69643
medium	8	111	13.875	54.98214
High	8	157	19.625	27.125
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	422.3333	2	211.1667	6.477269	0.00644	3.4668
Within Groups	684.625	21	32.60119
Total	1106.958	23