Your answer

asked 2021-05-08

For the poll described in the Chapter problem, assume that the respondents had been asked for their political party affiliation, and the responses were coded as 0 (for Democrat), 1 (for Republican), 2 (for Independent), or 3 (for any other response). If we calculate the average (mean) of the numbers and get 0.95, how can that value be interpreted?

asked 2021-08-07

Find the value:

\(\displaystyle{t}_{{{\frac{{{a}}}{{{2}}}}}}\)

\(\displaystyle{n}={23}\) for the \(\displaystyle{95}\%\) confidence interval for the mean.

\(\displaystyle{t}_{{{\frac{{{a}}}{{{2}}}}}}\)

\(\displaystyle{n}={23}\) for the \(\displaystyle{95}\%\) confidence interval for the mean.

asked 2021-11-27

Find mean and median for given data.

12,15,17,19,15,13,15,20,22,24,25,23,26,29,30

12,15,17,19,15,13,15,20,22,24,25,23,26,29,30

asked 2021-09-12

Suppose the ages of students in Statistics 101 follow a normal distribution with a mean of 23 years and a standard deviation of 3 years. If we randomly sampled 100 students, which of the following statements about the sampling distribution of the sample mean age is incorrect.

A) The expected value of the sample mean is equal to the population’s mean.

B) The standard deviation of the sampling distribution is equal to 3 years.

C) The shape of the sampling distribution is approximately normal.

D) The standard error of the sampling distribution is equal to 0.3 years.

A) The expected value of the sample mean is equal to the population’s mean.

B) The standard deviation of the sampling distribution is equal to 3 years.

C) The shape of the sampling distribution is approximately normal.

D) The standard error of the sampling distribution is equal to 0.3 years.

asked 2021-02-09

asked 2021-12-10

In a recent poll, 45% of survey respondents said that, if they only had one child, they would prefer the child to be a boy. Suppose you conducted a survey of 160 randomly selected students on your campus and find that 79 of them would prefer a boy. Complete parts (a) and (b) below.

Click here to view the standard normal distribution table (page 1).

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Click here to view the standard normal distribution table (page 2).

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(a) Use the normal approximation to the binomial to approximate the probability that, in a random sample of 160 students, at least 79 would prefer a boy, assuming the true percentage is 45%.

The probability that at least 79 students would prefer a boy is 3636.

(Round to four decimal places as needed.)

Click here to view the standard normal distribution table (page 1).

LOADING...

Click here to view the standard normal distribution table (page 2).

LOADING...

(a) Use the normal approximation to the binomial to approximate the probability that, in a random sample of 160 students, at least 79 would prefer a boy, assuming the true percentage is 45%.

The probability that at least 79 students would prefer a boy is 3636.

(Round to four decimal places as needed.)

asked 2021-10-14

Write a paragraph that describes the relationship between race (respondent's race) and cappun (opinion about capital punishment). Include a two-way table of counts and a relevant set of conditional percentages.