Question

7. What would be the correct Null-Hypothesis? (hint read end of lecture 24) (5 points) a. average annual number of tornadoes occurred until 1970 (inclusive) and average annual number of tornadoes occurred after 1970 are different. b. average annual number of tornadoes occurred until 1970 (inclusive) and average annual number of tornadoes occurred after 1970 are equal. c. average annual number of tornadoes occurred until 1970 (inclusive) and average annual number of tornadoes occurred after 1970 are related. d. average annual number of tornadoes occurred until 1970 (inclusive) and average annual number of tornadoes occurred after 1970 are not related.

Answer 1

The correct answer is d. average annual number of tornadoes occurred until 1970 (inclusive) and average annual number of tornadoes occurred after 1970 are not related.

Step-by-step explanation:

The purpose of a null hypothesis is to demonstrate that there is no statistical variation between two variables, or that one variable is not different from its mean.

A null hypothesis is taken as true until there is evidence that discredits it, thus giving rise to an alternative hypothesis, which is accepted as soon as the first one is annulled, and vice versa.

In other words, a null hypothesis is the one that proposes that two variables have nothing to do with each other, but rather it is more a matter of chance.