Understanding Experiments with Two Groups - Answer Key
Twenty Sets $1 =$

question 94

Short Answer

Understanding Experiments with Two Groups - Answer Key
Twenty sets of depressed twins are obtained for a study on the effects of a new antidepressant. In each twin set, one twin is assigned to receive the drug, and the other is designed to receive the placebo. Three months later, depression levels are measured on a scale from 1 (not at all depressed) to 7 (very depressed). The following data was obtained:
GROUP $1 =$ Received drug
GROUP $2 =$ Received placebo
Variable $=$ Depression level
$\begin{array} { l l l l } \text { GROUP } & N & \text { Mean } & S D \\ \text { GROUP 1 } & 10 & 3.21 & 1.035 \\ \text { GROUP 2 } & 10 & 5.77 & 1.772 \\ t = 5.785 & d f = 9 & p = 0.017 & \text { Cohen's } d = .88 \end{array}$
-What is the independent variable?

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Definitions:

Serial-Order Effect

a phenomenon observed in psychology where the position of an item in a sequence affects the likelihood of its recall.

Depth of Processing

A concept in cognitive psychology that describes how deeply information is thought about or processed, which affects memory retention.

Rhyme

A literary device wherein the ending sounds of words or lines are similar, commonly used in poetry and songs to create rhythm and aesthetic appeal.

Encoding Specificity Principle

A principle stating that the retrieval of information is more effective when the conditions at the time of recall match those present during the initial encoding or learning phase.