Questions from Statistics

Q: The principal claimed that the school’s mean SAT score was above 650

The principal claimed that the school’s mean SAT score was above 650. A hypothesis test seemed to back her up, but it later turned out that the mean score was exactly 650. Therefore, the test resulte...

Q: A significance level of 0.05 indicates that the probability of

A significance level of 0.05 indicates that the probability of making a type I error is 0.05.

Q: When a consumer group is testing the claim that the mean amount

When a consumer group is testing the claim that the mean amount of aspirin in tablets is 350 milligrams, it is extremely important not to wrongly reject a true null hypothesis. Thus, it is better to c...

Q: Because the significance level is the probability of making a type I

Because the significance level is the probability of making a type I error, it is wise to select a significance level of zero so that there is no chance of making that error.

Q: A handy mnemonic for interpreting the P-value in a hypothesis

A handy mnemonic for interpreting the P-value in a hypothesis test is this: “If the P (value) is low, then the null must go.”

Q: I used an exponential scale because the data values for my categories

I used an exponential scale because the data values for my categories ranged from 7 to 450,000,000.

Q: Find the value of the standard scores, z, and determine

Find the value of the standard scores, z, and determine whether to reject the null hypothesis at a 0.05 significance level. The critical values can be found in Tables 9.1 and 9.2. Is the alternative h...

Q: Find the value of the standard scores, z, and determine

Find the value of the standard scores, z, and determine whether to reject the null hypothesis at a 0.05 significance level. The critical values can be found in Tables 9.1 and 9.2. Is the alternative h...

Q: In testing the effectiveness of a new vaccine, suppose that researchers

In testing the effectiveness of a new vaccine, suppose that researchers used males for the treatment group and females for the placebo group. What is confounding, and how would it affect such an exper...

Q: Find the value of the standard scores, z, and determine

Find the value of the standard scores, z, and determine whether to reject the null hypothesis at a 0.05 significance level. The critical values can be found in Tables 9.1 and 9.2. Is the alternative h...