Which of the following conclusions seems most justified?

(a) The mean fear ratings increased from 1989to1991, because the slope of the least-squares line is positive.

(b) It appears that children with high fear ratings in 1989 had lower ratings in 1991.

(c) It appears that children with high fear ratings in1989had higher ratings in 1991.

(d) There is no evidence of a significant relationship between the mean fear ratings in 1989 and in 1991.

(e) There are sufficient inconsistencies in the data to make it impossible to draw any conclusions.

Short Answer

Expert verified

The correct answer is option (b) is it appears that children with high fear ratings in 1989had lower ratings in1991.

Step by step solution

01

Part (a) step 1: Given Information

We need to find the mean fear ratings increased from 1989to1991, because the slope of the least-squares line is positive.

02

Part (a) step 2: Explanation

By observing the given conclusion the mean fear ratings increased from 1989 to 1991, because the slope of the least-squares line is positive, not justified.

03

Part (b) step 1: Given Information 

We need to find It appears that children with high fear ratings in 1989 had lower ratings in 1991.

04

Part (b) step 2: Simplify

It appears the children with high fear ratings in 1989has lower ratings in 1991, because most children with a1989mean rating over2.0, so a1991mean rating below2.0.

05

Part (c) step 1: Given Information 

We need to find it appears that children with high fear ratings in1989had higher ratings in 1991.

06

Part (c) step 2: Explanation

By observing the given conclusion it appears that children with high fear ratings in1989had higher ratings in 1991 are not correct.

07

Part (d) step 1: Given Information 

We need to find there is no evidence of a significant relationship between the mean fear ratings in 1989and in 1991.

08

Part (d) step 2: Explanation

By observing the given conclusion there is no evidence of a significant relationship between the mean fear ratings in 1989and in 1991is not correct.

09

Part (e) step 1: Given Information

We need to find there are sufficient inconsistencies in the data to make it impossible to draw any conclusions.

10

Part (e) step 2: Explanation

By observing the given conclusion there are sufficient inconsistencies in the data to make it impossible to draw any conclusions not correct.

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