Which of the statements correctly compares t-distributions to the normal distribution?
I. t distributions are also mound shaped and symmetric.
II. t distributions have less spread than the normal distribution.
III. As degrees of freedom increase, the variance of t distributions becomes smaller.
A) I, II, and III
B) II only
C) I only
D) I and II only
E) I and III only

Question

Quizplus · Accepted Answer

I. True, t-distributions are mound-shaped and symmetric like the normal distribution. III. True, as the degrees of freedom increase, t-distributions approach the normal distribution, implying their variance becomes smaller and more similar to that of the normal distribution. II is incorrect because t-distributions have more spread (larger tails) than the normal distribution, especially with fewer degrees of freedom.

Which of the Statements Correctly Compares T-Distributions to the Normal