Question

Sensory isolation chambers are used to examine the effects of mild sensory deprivation. The chamber is a dark, silent tank where subjects float on heavily salted water and are thereby deprived of nearly all external stimulation. Sensory deprivation produces deep relaxation and had been shown to produce temporary increases in sensitivity for vision, hearing, touch, and even taste. The following data represent hearing threshold scores for a group of subjects who were tested before and immediately after one hour of deprivation. A lower score indicates more sensitive hearing. Do these data indicate that deprivation has a significant effect on hearing threshold? Test at the .05 level of significance with two tails. SHOW ALL WORK

Subject	Before	After
A	31	30
B	34	31
C	29	29
D	33	29
E	35	32
F	32	34
G	35	28

a) State symbolically what your H1 and H0 would be.

b) What kind of test would you use (One-sample, Related-samples, etc.)?

c) What is your df? What is your critical t?

d) Based on the above information, would you reject H0, or fail to reject it? Why? What would your conclusion be?

Answer 1

Let us denote the difference

d = score before - score after

b) One should use a paired t test.

Conclusion - There is sufficient evidence to conclude that deprivation has a significant effect on hearing threshold as score has been significantly decreased after deprivation.