A researcher randomly assigns 10 participants to a sample that will receive a treatment, and 10 participants to a control group. After receiving the treatment, sample 1 has a mean of M subscript 1 space equals space 25, S S subscript 1 space equals space 200. The control group has a mean of M subscript 2 space equals space 28, S S subscript 2 space equals space 160. Using a 1-tailed test and alpha alpha equals 0.05, can we conclude that the treatment had a significant effect?
Answer
Using TI 84 calculator
press stat then tests then 2-sampTTest
enter the data
x1 = 25
s1 = 200
n1 = 10
x2 = 28
s2 = 160
n2 = 10
Pooled: No
press enter, we get
t statistic = -0.037
p value = 0.5146
p value is greater than 0.05 significance level, so we failed to reject the null hypothesis
we can conclude that the treatment had no significant effect at 0.05 significance level
A researcher randomly assigns 10 participants to a sample that will receive a treatment, and 10...
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