Stat101 ch. 17

The p-value for a hypothesis test is 0.0232 and all conditions for the hypothesis test are met. What is the decision for this hypothesis test when x= 0.05

reject the null hypothesis

The sample proportion is the proportion of the [b] belonging to the category of interest.

sample

The [c] determines whether or not the p-value is small enough to reject the null hypothesis.

significance level

The [a] is used to test whether or not the null hypothesis is true.

test statistic

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.41 HA: p not equal to 0.41 All conditions are met for the hypothesis test, and the sample proportion from a sample of size 700 is 0.39. What is the z-test statistic for this hypothesis test?

z= -1.08

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.93 HA: p not equal to 0.93 All conditions are met for the hypothesis test, and the sample proportion from a sample of size 600 is 0.90. What is the z-test statistic for this hypothesis test?

z= -2.88

The [a] is the proportion of the population belonging to the category of interest.

population proportion

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.2 HA: p < 0.2 All conditions are met for the hypothesis test. Based on the sample proportion, the z-test statistic was calculated to be -2.32. What is the p-value for this test?

0.0102

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.2 HA: p not equal to 0.2 All conditions are met for the hypothesis test. Based on the sample proportion, the z-test statistic was calculated to be 2.57. What is the p-value for this test?

0.0102

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.2 HA: p > 0.2 All conditions are met for the hypothesis test. Based on the sample proportion, the z-test statistic was calculated to be 1.62. What is the p-value for this test?

0.0526

The null and alternative hypotheses for a particular hypothesis test are H0: p = 0.2 HA: p < 0.2 All conditions are met for the hypothesis test. The sample proportion is 0.172 with a p-value of 0.0409. Select the correct interpretation of this p-value.

The probability we would get a sample proportion of 0.172 or smaller if the null hypothesis is true is equal to 0.0409.

An ABC News Poll in 2004 surveyed 1,501 randomly selected U.S. adults and asked if they believed it is more enjoyable to be married or single. In the survey, 1,126 responded that they believe it is more enjoyable to be married than single. Is this enough evidence to conclude that more than 70% of American believe it is more enjoyable to be married than single? A z-test statistic and p-value were calculated for the correct null and alternative hypotheses. Based on the p-value and alpha level for the test, the decision was made to reject the null hypothesis. Given this information, select the correct conclusion of the hypothesis test below.

There is enough evidence to conclude the proportion of U.S. adults who believe it is more enjoyable to be married than single is greater than 0.7.

A large manufacturer that sells consumer products on-line wishes to publicize its customer satisfaction in an advertisement. Specifically, it wants to state that over 90% of the manufacturer's customers would tell a friend to buy a product from the manufacturer. The manufacturer selects a random sample of 400 customers from its database, contacts them via email and asks them the question "Would you tell a friend to buy a product from us?" 372 say yes and 28 say no. Is this enough evidence for the manufacturer to state that more than 90% of its customers would tell their friend to buy a product from the manufacturer? A z-test statistic and p-value were calculated for the correct null and alternative hypotheses. Based on the p-value and alpha level for the test, the decision was made to reject the null hypothesis. Given this information, select the correct conclusion of the hypothesis test below.

There is enough evidence to conclude the proportion of customers who would tell a friend to buy a product from the manufacturer is greater than 0.9.

In the 1980's it was generally believed around 5% of all children in the U.S. were affected by congenital abnormalities. Some people believe that the increase in chemicals in the environment has led to an increase in the proportion of children in the U.S. with congenital abnormalities. A recent study examined 384 randomly selected children in the U. S. and found that 23 had congenital abnormalities. Is this enough evidence to state the proportion of all children in the U.S. with congenital abnormalities is more than 0.05? A z-test statistic and p-value were calculated for the correct null and alternative hypotheses. Based on the p-value and alpha level for the test, the decision was made not to reject the null hypothesis. Given this information, select the correct conclusion of the hypothesis test below.

There is not enough evidence to conclude the proportion of all children in the U.S. affected by congenital abnormalities is greater than 0.05.

one-sided hypothesis (right-tailed)

p>p0

In conducting a hypothesis test, [a] p-values mean we have evidence against the null hypothesis and [b] p-values mean we have little to no evidence against the null hypothesis.

a) small b) large

The [f] is a claim you would like to prove about the value of the population proportion.

alternative hypothesis

The sampling distribution model for the sample proportion describes the behavior of the [c] in repeated sampling from the [d].

c) sample proportion d) population

The [f] states the results of the hypothesis test in the context of the problem.

conclusion

The [d] states simply whether or not to reject the [e].

d) decision e) null hypothesis

The p-value for a hypothesis test is 0.2212 and all conditions for the hypothesis test are met. What is the decision for this hypothesis test when x= 0.05

fail to reject the null hypothesis

The [e] specifies what the value of the population proportion is assumed to be.

null hypothesis

In the 1980's it was generally believed around 5% of all children in the U.S. were affected by congenital abnormalities. Some people believe that the increase in chemicals in the environment has led to an increase in the proportion of children in the U.S. with congenital abnormalities. A recent study examined 384 randomly selected children in the U. S. and found that 23 had congenital abnormalities. Is this enough evidence to state the proportion of all children in the U.S. with congenital abnormalities is more than 0.05? Specify the correct number from the list below that corresponds to the appropriate null and alternative hypotheses for this problem.

null: p = 0.05 alternative: p > 0.05

Researchers believe that 24.5% of the adults in the United States are obese. A Gallup poll examined the rate of obesity in America with a survey 86,664 randomly sampled U.S. adults. Of the adults surveyed, 23,053 said that they were obese. Is this enough evidence to state that more than 24.5% of all adults in the U.S. are obese? Specify the correct number from the list below that corresponds to the appropriate null and alternative hypotheses for this problem.

null: p = 0.245 alternative: p > 0.245

two-sided hypothesis (two-tailed)

p not equal to p0

The [b] is the probability of obtaining a value of the test statistic equal to or more extreme than the observed value if the null hypothesis is true.

p-value

one-sided hypothesis (left-tailed)

p<p0

Null hypothesis

p=p0