Question

A researcher determined that the correlation between height in inches and 50 yard dash time in seconds for 123 eleven year old boys in a city recreation program was -.51. Which statement below is the best interpretation of this findinf?

a. As height increases, this CAUSES speed to decrease

b. Tall boys run faster than short boys over 50% of the time

c. There is some tendancy for dash scores to decrease as height increases

d. There is a very poir relationship between height and dash scores since the correlation is negative

e. the taller the person the larger tends to be his dash score

Answer 1

Negative correlation in the given problem indicates that there is an inverse relationship between height and dash time. So, as height increases, dash time decreases and vice-versa.

Option a: As height increases, this CAUSES speed to decrease

This is incorrect because in statistics, we cannot declare one variable to certainly be the CAUSE of change in value of another.

Option b: Tall boys run faster than short boys over 50% of the time

This is also incorrect because the value of -0.51 correlation just means that height accounts for more than 50 percent of the variance in dash time.

Option c: There is some tendancy for dash scores to decrease as height increases

This is correct as we established in the beginning above that there is an inverse relationship between height and dash time.

Option d is wrong since the relation is quite established and not poor.

Option e is wrong since taller person has lower dash score.