Which statement about re-expressing data is true?
I. Unimodal distributions that are skewed to the left can be made more symmetric by taking the square root of the variable.
II. A curve that is descending as the explanatory variable increases may be straightened by taking a logarithm of the response variable.
III. One goal of re-expression may be to make the variability of the response variable more uniform.
A) I only
B) II only
C) III only
D) II and III
E) I, II and III

Question

Quizplus · Accepted Answer

I is not true because taking the square root of a variable will not always make a skewed distribution more symmetric. II is true because taking the logarithm of the response variable may straighten a curve that is descending as the explanatory variable increases. III is true because re-expressing data can be used to make the variability of the response variable more uniform. Therefore, II and III are the best choices.

Which Statement About Re-Expressing Data Is True