When Testing the Difference Between the Means of a Treatment

question 43

Essay

When testing the 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)represents a population whose mean is different from the mean for the untreated population? Explain. $$\begin{array} { | l | l | l | l | } \hline & \text { t-Test: Two Sample for Means } & & \\\hline 1 & & \text { Variable 1 } & \text { Variable 2 } \\\hline 2 & \text { Mean } & 171.6392 & 168.7718 \\\hline 3 & \text { Known Variance } & 47.51672 & 41.08293 \\\hline 4 & \text { Observations } & 50 & 50 \\\hline 5 & \text { Hypothesized Mean Difference } & 0 & \\\hline 6 & \text { t } & 2.154057 & \\\hline 7 & \text { P(T>=t) one-tail } & 0.0158 & \\\hline 8 & \text { TCritical one-tail } & 1.644853 & \\\hline 9 & \text { P(T>=t) two-tail } & 0.0316 & \\\hline 10 & \text { tCritical two-tail } & 1.959961 & \\\hline\end{array}$$

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Definitions:

Psychology Of Persuasion

The study of how individuals influence others' beliefs, attitudes, and behaviors through communication and other techniques.

Implicit Theory

Beliefs or assumptions that individuals hold about how certain traits, behaviors, and personality characteristics are interrelated and can change over time.

Primacy Effect

The psychological principle that items or information presented early in a list are remembered better than those presented later.

Unified Impression

An overall perception or interpretation that integrates various aspects into a coherent whole.