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 µ_{1}
and µ_{2} 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...

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