Module 3

Question 1

We use _________ to substantiate a claim about a population _____ (or other population parameter).

Answer 1

hypothesis tests; mean

Question 2

The ___________ is a statement about a topic of interest about the population. It is typically based on historical information or conventional wisdom.

Answer 2

null hypothesis (H0)

Question 3

We always start a hypothesis test by assuming that the null hypothesis is _____ and then test to see if we can nullify it using evidence from a _____.

Answer 3

true; sample

Question 4

The null hypothesis is the ______ of the hypothesis we are trying to ______ (the alternative hypothesis).

Answer 4

opposite; prove

Question 5

The ___________ is the theory or claim we are trying to substantiate.

Answer 5

alternative hypothesis (Ha)

Question 6

When should the following be done?

• Determine whether to analyze a change in a single population or compare two populations.
• Determine whether to perform a one-sided or two-sided hypothesis test.

Answer 6

Before conducting a hypothesis test

Question 7

To conduct a hypothesis test, we must follow these steps:
• _____ the null and alternative hypotheses.
• Choose the _________ for the test.
• Gather _____ about a sample or samples.
• To determine whether the sample is highly unlikely under the assumption that the null hypothesis is true,
construct the range of likely sample means or calculate the _____.

Answer 7

State; level of significance; data; p-value

Question 8

The p-value is the likelihood of obtaining a sample as extreme as the one we’ve obtained, if the null
hypothesis is ____.

Answer 8

true

Question 9

The p-value of a one-sided hypothesis test is ____the p-value of a two-sided hypothesis test.

Answer 9

half

Question 10

If the sample mean falls in the range of likely sample means, or if its p-value is _______ the stated
significance level, we do not have sufficient evidence to reject the null hypothesis.

Answer 10

greater than

Question 11

If the sample mean falls in the rejection region, or if it has a p-value ________ the stated significance level, we have sufficient evidence to reject the null hypothesis.

Answer 11

lower than

Question 12

We can __________ the null hypothesis.

Answer 12

never accept

Question 13

What type of error is associated with - the higher the confidence level (and therefore the lower the significance level), the lower the chance of rejecting the null hypothesis when it is true?

Answer 13

type I error or false positive

Question 14

What type of error is associated with - the higher the confidence level, the higher the chance of not rejecting it when it is false?

Answer 14

type II error or false negative

Question 15

How do you calculate the range of likely sample means?

Answer 15

using CONFIDENCE.NORM or CONFIDENCE.T

Question 16

Which function returns the p-value associated with a given t-test?

Answer 16

=T.TEST(array1, array2, tails, type)

Question 17

What are tails?

Answer 17

tails is the number of tails for the distribution. It should be set to 1 to perform a one-sided test; to 2 to perform
a two-sided test.

Question 18

Which type do we usually use?

Answer 18

Type 3 is an unpaired test in which the samples are assumed to have unequal variances. Unless we have
a good reason to believe two samples have equal variances, we typically use type 3 when conducting an
unpaired test.