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Chapter 10: Q. 12 (page 668)

The correlation between the heights of fathers and the heights of their (grownup) sons isr=0.52 , both measured in inches. If fathers鈥� heights were measured in feet and sons鈥� heights were measured in furlongs (one furlong equals 7920 inches), the correlation between heights of fathers and heights of sons would be

(a) much smaller than 0.52.

(b) slightly smaller than 0.52.

(c) unchanged; equal to 0.52.

(d) slightly larger than 0.52.

(e) much larger than 0.52.

Short Answer

Expert verified

The answer is an option (c) unchanged; equal to 0.52

Step by step solution

01

Given Information

The correlation between the heights of fathers and the heights of their (grownup) sons is r=0.52, both measured in inches.

And, one furlong equals 7920 inches.

02

Explanation. 

The advantage of correlation is it's a unitless measure. If changing one of the unit measures (from feet to furlongs) resulted in a correlation change, then the value would be arbitrary since we have arbitrarily defined the units. Then, the correlation would never have any practical meaning.

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