
Concept explainers
(a)
To explain is there a clear pattern and describe the trend.
(a)

Answer to Problem 1E
Yes.
Explanation of Solution
The researcher wants to know that is the age of women get married has changed over the past years or not. The
(b)
To explain is the association strong or not.
(b)

Answer to Problem 1E
Yes, it is strong.
Explanation of Solution
The researcher wants to know that is the age of women get married has changed over the past years or not. The scatterplot given in the question shows the trend in age at first marriage for American women. By looking at the scatterplot, we can say that the association is strong as the points in the scatterplot shows the clear pattern and are in upward direction.
(c)
To explain is the association high or not.
(c)

Answer to Problem 1E
No, it is not high.
Explanation of Solution
The researcher wants to know that is the age of women get married has changed over the past years or not. The scatterplot given in the question shows the trend in age at first marriage for American women. From looking at the scatterplot of women’s age at first marriage with years we can say that the association is not high as the graph is non-linear between the years.
(d)
To explain is the linear model appropriate or not.
(d)

Answer to Problem 1E
No, it is not appropriate.
Explanation of Solution
The researcher wants to know that is the age of women get married has changed over the past years or not. The scatterplot given in the question shows the trend in age at first marriage for American women. The linear model is not appropriate because the graph has the curve in it so, a linear model would not give accurate results.
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