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Chapter 4: Q 46. (page 253)

Child care and aggression A study of child care enrolled 1364infants and followed them through

their sixth year in school. Later, the researchers published an article in which they stated that 鈥渢he more time children spent in child care from birth to age four-and-a-half, the more adults tended to rate them, both at age four-and-a-half and at kindergarten, as less likely to get along with others, as more assertive, as disobedient, and as aggressive.鈥�

(a) Is this an observational study or an experiment? Justify your answer.

(b) What are the explanatory and response variables?

(c) Does this study show that child care causes children to be more aggressive? Explain.

Short Answer

Expert verified

Part (a) Observational study.

Part (b) Adult assessments of their behavior have become the response variable.

Part (c) No, there is chance lurking variable.

Step by step solution

01

Part (a) Step 1: Given information 

Number of infants, n=1364

02

Part (a) Step 2: Concept

Observational research looks at people and assesses factors of interest without trying to affect their responses.

03

Part (a) Step 3: Explanation

This was an observational study in which an observer analysis was used to gather information on the possible influence of therapy on individuals when they were randomly allocated to a treated or control group. The researchers followed them throughout their sixth grade year and had adults evaluate their behaviour.

04

Part (b) Step 1: Explanation

Adult ratings can be explained since time spent in childcare between the ages of 4 and 1/2 can be clarified. From birth until the age of four and a half, the explanatory variable in childcare was the amount of time. The response variable is now adult judgements of their behaviour.

05

Part (c) Step 1: Explanation

No. This study cannot conclude that childcare makes children more violent because it is an observational study that cannot infer cause and effect; an unknown variable may exist that causes their conduct to vary in adult ratings.

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