Question

A researcher used an independent sample t test to compare two treatment conditions. He wanted to test whether there is a significant difference between two treatments. Following data were obtained:

Treatment one group: # of participants = 12, sample mean = 55, sample standard dev (s) = 2.83

Treatment two group: # of participants = 12, sample mean = 52, sample standard dev (s) = 2.00

Use 5% significance level. Assume µ1 and µ2 are the population means for group one and two respectively.

a) What is null and alternative hypotheses?

b) What is the value of the test statistic?

c) What is the p-value?

d) What is your conclusion?

Answer #1

A researcher used an independent sample t test to compare two
treatment conditions. He wanted to test whether there is a
significant difference between two treatments. Following data were
obtained:
Treatment one group: # of participants = 12, sample mean = 55,
sample standard dev (s) = 2.83
Treatment two group: # of participants = 12, sample mean = 52,
sample standard dev (s) = 2.00
Use 5% significance level.
Assume µ1
and µ2 are the population means for group one
and...

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1a)
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a.
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A researcher performed a independent sample t test to
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Treatment A
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12
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Write a simulation in R that shows the distribution of the
t-‐test statistic for a two-‐sample t test when the null
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