Question 1

As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution when
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Accepted Answer

The answer of As a rule of thumb, the sampling...

Question 2

A student wants to determine if pennies are really fair, meaning equally likely to land heads up or tails up. He flips a random sample of 50 pennies and finds that 28 of them land heads up. What are the appropriate null and alternative hypotheses? A)H₀: p ≥ 0.5, H_{a :}_{p < 0.5} B)H₀: p ≤ 0.5, H_{a :}_{p ≠ 0.5} C)H₀: p = 0.5, H_{a :}_{p > 0.5} D)H₀: p ≥ 28, H_{a :}_{p < 28}

Accepted Answer

The appropriate null hypothesis is that the probability of a penny landing heads up is 0.5, and the alternative hypothesis is that the probability is greater than 0.5. This is because we want to test whether pennies are fair (equally likely to land heads up or tails up), and if they are fair, the probability of a penny landing heads up should be 0.5. We do not have enough evidence to support the alternative hypothesis that the probability is less than 0.5, so option A is incorrect. The alternative hypothesis in option B is too vague, and does not specify whether the probability is greater or less than 0.5, so it is also incorrect. Option D is incorrect because the null hypothesis should be a specific value, not based on the sample proportion.

Question 3

A sample of 92 observations is taken from an infinite population. The sampling distribution of is approximately normal because of what theorem?
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Accepted Answer

The answer of A sample of 92 observations is taken...

Question 4

You are _______________ to commit a Type I error using the 0.05 level of significance than using the 0.01 level of significance.
A)more likely
B)less likely
C)equally likely
D)twice as likely

Accepted Answer

The 0.05 level of significance allows for a higher probability of rejecting the null hypothesis when it is actually true, which increases the likelihood of committing a Type I error. Therefore, it is more likely to commit a Type I error at the 0.05 level than the 0.01 level.

Question 5

What is the general form of an interval estimate?
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Accepted Answer

The answer of What is the general form of an...

Question 6

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07.The value of 126.07 is symbolized by.
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Accepted Answer

The answer of The medical director of a company looks...

Question 7

Numerical characteristics of the population are called
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Accepted Answer

The answer of Numerical characteristics of the population are called
​...

Question 8

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H_o: μ = 11 H_a: μ > 11 A)left-tailed. B)right-tailed. C)two-tailed. D)there is not enough information to make a determination.

Accepted Answer

The alternative hypothesis H_a: μ > 11 indicates a right-tailed test because it is testing if the mean is greater than 11.

Question 9

Which statement is NOT true? ​​
A)Rejecting the null hypothesis when it is true is a Type I error.
B)The probability of making a Type I error is symbolized by α.
C)Failing to reject the null hypothesis when it is false is a Type I error.
D)Type II error can occur for both one and two-tailed tests.

Accepted Answer

Failing to reject the null hypothesis when it is false is actually a Type II error, not a Type I error. In a Type II error, we fail to reject the null hypothesis when it is actually false, leading to a missed opportunity to detect a real effect. Type I error occurs when we reject the null hypothesis when it is actually true.

Question 10

The sample mean is the point estimator of what population parameter?
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Accepted Answer

The answer of The sample mean is the point estimator...

Question 11

Statistical significance at the 0.01 level is___________ than significance at the 0.05 level .
A)more difficult to achieve
B)easier to achieve
C)less costly
D)less informative

Accepted Answer

Statistical significance at the 0.01 level is more difficult to achieve because it requires stronger evidence to reject the null hypothesis compared to significance at the 0.05 level. This means that the results must be more extreme or precise to achieve significance at the 0.01 level.

Question 12

A simple random sample of 11 observations from a population containing 400 female soccer players was taken, and the following values were obtained.
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48 53 72 56 63 64 56 76 50 46 73
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What is the value of the point estimate of the population mean?

Accepted Answer

The answer of A simple random sample of 11 observations...

Question 13

A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were determined to be 80 and 12 respectively. Calculate the standard error of the mean.
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Accepted Answer

The answer of A simple random sample of 100 observations...

Question 14

It is impossible to construct a sampling frame for an __________ population
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Accepted Answer

The answer of It is impossible to construct a sampling...

Question 15

Sample statistics, such as , s, or , that provide an estimate of the population parameter are known as
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Accepted Answer

The answer of Sample statistics, such as , s, or...

Question 16

As the sample size increases, the standard error of the mean ______________.
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Accepted Answer

The answer of As the sample size increases, the standard...

Question 17

Random samples of size 100 are taken from an infinite population whose population proportion is 0.2. The mean and standard deviation of the sample proportion are?
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Accepted Answer

The answer of Random samples of size 100 are taken...

Question 18

A random sample of 150 people was taken from a very large population. Ninety of the people in the sample were female. What is the standard error of the proportion?
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Accepted Answer

The answer of A random sample of 150 people was...

Question 19

A cellular phone company claims that the mean amount spent per month is more than $75. A test is made of H_o: μ = 75 versus H_a: μ > 75. The null hypothesis is rejected. State the appropriate conclusion.

Accepted Answer

The answer of A cellular phone company claims that the...

Question 20

Which statement is NOT true? ​​
A)The greater the level of confidence, the more likely it is that the confidence interval actually includes the true population mean.
B)The greater the level of confidence, the larger the z-score.
C)The greater the level of confidence, the wider the confidence interval.
D)Rejecting the null hypothesis when it is true is a Type II error.

Accepted Answer

Rejecting the null hypothesis when it is true is defined as a Type I error, not a Type II error. A Type II error occurs when failing to reject the null hypothesis when it is false.

Quiz 6: Statistical Inference

As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution when

A student wants to determine if pennies are really fair, meaning equally likely to land heads up or tails up. He flips a random sample of 50 pennies and finds that 28 of them land heads up. What are the appropriate null and alternative hypotheses?

A sample of 92 observations is taken from an infinite population. The sampling distribution of is approximately normal because of what theorem?

You are _______________ to commit a Type I error using the 0.05 level of significance than using the 0.01 level of significance.

What is the general form of an interval estimate?

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07.The value of 126.07 is symbolized by.

Numerical characteristics of the population are called

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H_o: μ = 11 H_a: μ > 11

Which statement is NOT true?

The sample mean is the point estimator of what population parameter?

Statistical significance at the 0.01 level is___________ than significance at the 0.05 level .

A simple random sample of 11 observations from a population containing 400 female soccer players was taken, and the following values were obtained. 48 53 72 56 63 64 56 76 50 46 73 What is the value of the point estimate of the population mean?

A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were determined to be 80 and 12 respectively. Calculate the standard error of the mean.

It is impossible to construct a sampling frame for an __________ population

Sample statistics, such as , s, or , that provide an estimate of the population parameter are known as

As the sample size increases, the standard error of the mean ______________.

Random samples of size 100 are taken from an infinite population whose population proportion is 0.2. The mean and standard deviation of the sample proportion are?

A random sample of 150 people was taken from a very large population. Ninety of the people in the sample were female. What is the standard error of the proportion?

A cellular phone company claims that the mean amount spent per month is more than $75. A test is made of H_o: μ = 75 versus H_a: μ > 75. The null hypothesis is rejected. State the appropriate conclusion.

Which statement is NOT true?

Quiz 6: Statistical Inference

As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution when ​

A student wants to determine if pennies are really fair, meaning equally likely to land heads up or tails up. He flips a random sample of 50 pennies and finds that 28 of them land heads up. What are the appropriate null and alternative hypotheses?

A sample of 92 observations is taken from an infinite population. The sampling distribution of is approximately normal because of what theorem? ​

You are _______________ to commit a Type I error using the 0.05 level of significance than using the 0.01 level of significance.

What is the general form of an interval estimate? ​

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07.The value of 126.07 is symbolized by. ​ ​

Numerical characteristics of the population are called ​

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: Ho: μ = 11 Ha: μ > 11

Which statement is NOT true? ​​

The sample mean is the point estimator of what population parameter? ​

Statistical significance at the 0.01 level is___________ than significance at the 0.05 level .

A simple random sample of 11 observations from a population containing 400 female soccer players was taken, and the following values were obtained. ​ 48 53 72 56 63 64 56 76 50 46 73 ​ What is the value of the point estimate of the population mean?

A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were determined to be 80 and 12 respectively. Calculate the standard error of the mean. ​

It is impossible to construct a sampling frame for an __________ population ​

Sample statistics, such as , s, or , that provide an estimate of the population parameter are known as ​

As the sample size increases, the standard error of the mean ______________. ​

Random samples of size 100 are taken from an infinite population whose population proportion is 0.2. The mean and standard deviation of the sample proportion are? ​

A random sample of 150 people was taken from a very large population. Ninety of the people in the sample were female. What is the standard error of the proportion? ​

A cellular phone company claims that the mean amount spent per month is more than $75. A test is made of Ho: μ = 75 versus Ha: μ > 75. The null hypothesis is rejected. State the appropriate conclusion. ​

Which statement is NOT true? ​​

As a rule of thumb, the sampling distribution of the sample proportions can be approximated by a normal probability distribution when

A sample of 92 observations is taken from an infinite population. The sampling distribution of is approximately normal because of what theorem?

What is the general form of an interval estimate?

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07.The value of 126.07 is symbolized by.

Numerical characteristics of the population are called

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H_o: μ = 11 H_a: μ > 11

Which statement is NOT true?

The sample mean is the point estimator of what population parameter?

A simple random sample of 11 observations from a population containing 400 female soccer players was taken, and the following values were obtained. 48 53 72 56 63 64 56 76 50 46 73 What is the value of the point estimate of the population mean?

A simple random sample of 100 observations was taken from a large population. The sample mean and the standard deviation were determined to be 80 and 12 respectively. Calculate the standard error of the mean.

It is impossible to construct a sampling frame for an __________ population

Sample statistics, such as , s, or , that provide an estimate of the population parameter are known as

As the sample size increases, the standard error of the mean ______________.

Random samples of size 100 are taken from an infinite population whose population proportion is 0.2. The mean and standard deviation of the sample proportion are?

A random sample of 150 people was taken from a very large population. Ninety of the people in the sample were female. What is the standard error of the proportion?

A cellular phone company claims that the mean amount spent per month is more than $75. A test is made of H_o: μ = 75 versus H_a: μ > 75. The null hypothesis is rejected. State the appropriate conclusion.

Which statement is NOT true?