Q: Which of the following best describes a two-tailed test?

The alternative hypothesis is $$H_a: \mu \neq \mu_0$

Question 1

Which of the following best describes the null hypothesis ($$H_0) in $$hypothesis testing?

Accepted Answer

It is a statement that there is no effect or no difference.

Question 2

A snack company claims their bags contain 454 g of cookies. The quality assurance department wants to test if the mean net weight is different from 454 g. What is the correct alternative hypothesis ($$H_a$$)?

Accepted Answer

$$H_a: \mu 
eq 454$$

Question 3

Which of the following statements about the p-value is correct?

Accepted Answer

A small p-value indicates strong evidence against the null hypothesis.

Question 4

Suppose you are testing $$H_0$$: \mu = 100$$ against H_a$$: \mu \u003e 100$$. Which type of test is this?

Accepted Answer

Right-tailed test

Question 5

A researcher wants to know if a new medication decreases blood pressure below the current average of 120 mmHg. What is the correct form of the alternative hypothesis?

Accepted Answer

$$H_a: \mu \u003c 120$$

Question 6

Which of the following is NOT a possible conclusion in hypothesis testing?

Accepted Answer

Accept the alternative hypothesis

Question 7

If the significance level is $$\alpha = 0.05$$ and the p-value is $$0.03$$, what should you conclude?

Accepted Answer

Reject the null hypothesis

Question 8

Which of the following best describes a two-tailed test?

Accepted Answer

The alternative hypothesis is $$H_a: \mu 
eq \mu_0$

Question 9

A university bookstore wants to test if the mean price of history books has increased from last year's mean of $$\76.01$. What is the null hypothesis?

Accepted Answer

$$H_0$$: \mu = 76.01$$

Question 10

Which of the following steps is NOT part of the P-value approach to hypothesis testing?

Accepted Answer

Accept the null hypothesis if the p-value is large

Question 11

A sample of 30 randomly selected books shows a mean price of $$\81.44$ with a population standard deviation of $$\$$8.71. If $$the null hypothesis is $$H_0$$: \mu = 76.01$$, what is the value of the test statistic z$?

Accepted Answer

$$z = \frac{81.44 - 76.01}{8.71 / \sqrt{30}}$$

Question 12

Which of the following best describes the purpose of the alternative hypothesis ($$H_a$$)?

Accepted Answer

To provide a statement that is contradictory to the null hypothesis

Question 13

If a test is designed to determine whether the mean is less than a specified value, what type of test is it?

Accepted Answer

Left-tailed test

Question 14

Which of the following is the correct formula for the test statistic $$z$$ when testing a population mean with known standard deviation?

Accepted Answer

$$z = \frac{\bar{x} - \mu_0$}{\sigma / \sqrt{n}}$$

Question 15

A p-value is best described as:

Accepted Answer

The probability of obtaining a result as extreme or more extreme than the observed, assuming the null hypothesis is true

Question 16

Which of the following is a correct interpretation if you fail to reject the null hypothesis?

Accepted Answer

There is not enough evidence to support the alternative hypothesis

Question 17

In a hypothesis test, what does the significance level $$\alpha$$ represent?

Accepted Answer

The probability of rejecting the null hypothesis when it is true

Question 18

A company wants to test if the mean weight of their product is greater than 500 g. Which is the correct form of the alternative hypothesis?

Accepted Answer

$$H_a: \mu \u003e 500$$

Question 19

Which of the following is a correct step in the process of hypothesis testing?

Accepted Answer

State the null and alternative hypotheses

Question 20

If the sample data provides substantial contradictory evidence to the null hypothesis, what should you do?

Accepted Answer

Reject the null hypothesis

Hypothesis Testing and Significance in Statistics

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