Which statement correctly compares t-distributions to the normal distribution?
I. t-distributions are also unimodal, mound shaped and symmetric.
II. t-distributions have more spread than the normal distribution.
III. As degrees of freedom decrease, the variance of t-distribtuions becomes smaller.
1. II only
2. I and II only
3. I only
4. I and III only
III is not correct. With more degrees of freedom (really estimates of mean with more samples) its variance decreases.
II is true - the t-distribution has larger tails than the normal distribution and its peak is smaller.
I is also true - the t-distribution is symmertic, mound shaped and unimodal (have one maximum)
so 2 it is.
Content will be erased after question is completed.
Enter the email address associated with your account, and we will email you a link to reset your password.
Forgot your password?