Between 20 and 25 violent acts are portrayed per hour on children’s TV. A study by...

Between 20 and 25 violent acts are portrayed per hour on children’s TV. A study by Johnson et al (2002) looked for links between TV viewing and aggression by following the TV viewing habits of children 1-10 years old. Of these, 88 watched < 1 hr TV per day, 386 watched 1-3 hrs and 233 watched > 3 hrs. Eight years later, researchers looked to see if any of the children had records of aggressive assaults on other people. The numbers of children with aggressive assaults were 5, 87 and 67 for each TV category, respectively. The remaining children were not aggressive.

Question 1: Create a contingency table of the results from the study. Carry out an appropriate statistical test to determine whether TV viewing is associated with future violence. What is the conclusion from your test?

Question 2: Do the results of the study prove that TV watching behavior causes increased aggression in children? Why?

Solutions

Expert Solution

Chi-Square Test of independence
	Observed Frequencies
	0
0	aggressive	not aggressive	Total
<1hours	5	83	88
1-3hours	87	299	386
<3hours	67	166	233



Total	159	548	707

	Expected frequency of a cell = sum of row*sum of column / total sum
	Expected Frequencies
	aggressive	not aggressive	Total
<1hours	159*88/707=19.791	548*88/707=68.209	88
1-3hours	159*386/707=86.809	548*386/707=299.191	386
<3hours	159*233/707=52.4	548*233/707=180.6	233



Total	159	548	707

	(fo-fe)^2/fe
<1hours	11.054	3.207
1-3hours	0.000	0.000
<3hours	4.0678	1.1802

Chi-Square Test Statistic,χ² = Σ(fo-fe)^2/fe =   19.510

Level of Significance =   0.05
Number of Rows =   3
Number of Columns =   2
Degrees of Freedom=(#row - 1)(#column -1) = (3- 1 ) * ( 2- 1 ) =   2

p-Value =   0.0001   [Excel function: =CHISQ.DIST.RT(χ²,df) ]
Decision:    p-value < α , Reject Ho

so,
TV viewing is associated with future violence

.......................

results of the study prove that TV watching behavior causes increased aggression in children

as TV viewing is associated with future violence

....................

Please revert back in case of any doubt.

Please upvote. Thanks in advance.

orchestra answered 1 year ago

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