When Testing for a Difference Between the Means of a Treatment

question 9

Essay

When testing for a difference between the means of a treatment group and a placebo group, the
computer display below is obtained. Using a 0.05 significance level, is there sufficient evidence
to support the claim that the treatment group (variable 1)comes from a population with a mean
that is less than the mean for the placebo population? Explain. $\text { t-Test: Two Sample for Means }$
$\begin{array}{|l|l|l|l|}\hline 1 & & {\text { Variable 1 }} & \text { Variable 2 } \\\hline 2 & \text { Mean } & 65.10738 & 66.18251 \\\hline 3 & \text { Known Variance } & 8.102938 & 10.27387 \\\hline 4 & \text { Observations } & 50 & 50 \\\hline 5 & \text { Hypothesized Mean Difference } & 0 & \\\hline 6 & t & -1.773417 & \\\hline 7 & P(T<=t) \text { one-tail } & 0.0384 & \\\hline 8 & T \text { Critical one-tail } & 1.644853 & \\\hline 9 & P(T<=t) \text { two tail } & 0.0768 & \\\hline 10 & t \text { Critical two-tail } & 1.959961 & \\\hline\end{array}$

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Definitions:

General Reasoning Ability

The capacity to understand logical principles, solve problems, and make sense of complex information.

Stimulus Card

A card or visual aid used in psychological experiments or assessments to elicit responses from participants.

Normed

Refers to the process of standardizing a test by administering it to a large, representative sample and using the results as a norm for interpreting scores.

Translated Version

Refers to a version of a document, tool, or piece of content that has been converted from one language to another.