A Team of Cognitive Psychologists Studying the Effects of Sleep

question 63

Essay

A team of cognitive psychologists studying the effects of sleep deprivation on short-term memory decay had eight participants stay in a sleep lab for two days.Four participants were randomly assigned to a condition in which they were not permitted to sleep during that period,while the other four participants were allowed to sleep when they wanted to.At the end of the two days,the participants completed a short-term memory task that yielded the results in the table that follows.Using the .05 significance level,did sleep deprivation reduce short-term memory? a.Use the five steps of hypothesis testing.
b.Sketch the distributions involved.
c.Figure the effect size.
d.Explain the logic of what you did to a person who is familiar with the t test for a single sample,but who is unfamiliar with the t test for independent means.Be sure you explain how this problem differs from a t test for a single sample.Your answer should consist mainly of a thorough explanation of the characteristics of the comparison distribution and the logic of all the steps of figuring you did to determine those characteristics.

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Definitions:

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