SOPHIA PATHWAYS Introduction to Statistics milestone 5

Discipline: Statistics

Paper Format: APA

Pages: 1 Words: 275

Question

1

The data below shows the grams of fat for a variety of snacks. Morris wants to calculate the standard error of the sample mean for this set of data.

 Snack Grams of Fat Snack 1 9 Snack 2 13 Snack 3 21 Snack 4 30 Snack 5 31 Snack 6 31 Snack 7 34 Snack 8 25 Snack 9 28 Snack 10 20

What is the standard error for this set of data?

2

A researcher has a table of data with 5 column variables and 4 row variables.

The value for the degrees of freedom in order to calculate the  statistic is __________.

3

Rachel measures the lengths of a random sample of 100 screws. The mean length was 2.6 inches, with a standard deviation of 1.0 inches.

Using the alternative hypothesis (µ < µ0), Rachel found that a z-test statistic was equal to -1.25.

What is the p-value of the test statistic?  Answer choices are rounded to the thousandths place.

4

What do the symbols , , and  represent?

5

Which of the following is an example of a parameter?

6

Amanda is the owner of a small chain of dental offices. She sent out the yearly satisfaction survey to 600 randomly selected patients and received 544 surveys back. When looking through the results, she noticed that the downtown dental office staff had 84% of clients reporting satisfaction with services, while the uptown dental office staff had 76% of clients reporting satisfaction with services.

Which of the following sets shows Amanda's null hypothesis and alternative hypothesis?

7

For a left-tailed test, the critical value of z so that a hypothesis test would reject the null hypothesis at 10% significance level would be __________.  Answer choices are rounded to the hundredths place.

8

Sukie interviewed 125 employees at her company and discovered that 21 of them planned to take an extended vacation next year.

What is the standard error of the sample proportion?  Answer choices are rounded to the thousandths place.

9

One condition for performing a hypothesis test is that the observations are independent.  Mary is going to take a sample from a population of 500 students.

How many students will Mary have to sample without replacement to treat the observations as independent?

10

Select the statement that correctly describes a Type I error.

11

Edwin conducted a survey to find the percentage of people in an area who smoked regularly. He defined the label “smoking regularly” for males smoking 30 or more cigarettes in a day and for females smoking 20 or more. Out of 635 persons who took part in the survey, 71 are labeled as people who smoke regularly.

What is the 90% confidence interval for this population proportion?  Answer choices are rounded to the hundredths place.

12

Carl recorded the number of customers who visited his new store during the week:

 Day Customers Monday 17 Tuesday 13 Wednesday 14 Thursday 16

He expected to have 15 customers each day. To answer whether the number of customers follows a uniform distribution, a chi-square test for goodness of fit should be performed. (alpha = 0.10)

What is the chi-squared test statistic?  Answers are rounded to the nearest hundredth.

13

A ball is drawn from a bag of 26 red and 12 yellow balls. The process is repeated 50 times, replacing each ball that is drawn.

Which of the following statements about the distributions of counts and proportions is TRUE?

14

Edwin conducted a survey to find the percentage of people in an area who smoked regularly. He defined the label “smoking regularly” for males smoking 30 or more cigarettes in a day and for females smoking 20 or more. Out of 635 people who took part in the survey, 71 are labeled as people who smoke regularly.

Edwin wishes to construct a significance test for his data. He finds that the proportion of chain smokers nationally is 14.1%.

What is the z-statistic for this data?  Answer choices are rounded to the hundredths place.

15

Joe is measuring the widths of doors he bought to install in an apartment complex. He measured 72 doors and found a mean width of 36.1 inches with a standard deviation of 0.3 inches. To test if the doors differ significantly from the standard industry width of 36 inches, he computes a z-statistic.

What is the value of Joe's z-test statistic?

16

Adam tabulated the values for the average speeds on each day of his road trip as 60.5, 63.2, 54.7, 51.6, 72.3, 70.7, 67.2, and 65.4 mph. He wishes to construct a 98% confidence interval.

What value of t* should Adam use to construct the confidence interval?  Answer choices are rounded to the thousandths place.

17

What value of z* should be used to construct a 98% confidence interval of a population mean? Answer choices are rounded to the thousandths place.

18

Joe hypothesizes that the students of an elite school will score higher than the general population. He records a sample mean equal to 568 and states the hypothesis as μ  = 568 vs μ > 568.

What type of test should Joe do?

19

The data below shows the grams of fat in a series of popular snacks.

 Snack Grams of Fat Snack 1 9 Snack 2 13 Snack 3 21 Snack 4 30 Snack 5 31 Snack 6 31 Snack 7 34 Snack 8 25 Snack 9 28 Snack 10 20

If Morris wanted to construct a one-sample t-statistic, what would the value for the degrees of freedom be?

20

A table represents the number of students who passed or failed an aptitude test at two different campuses.

 East Campus West Campus Passed 48 37 Failed 52 63

In order to determine if there is a significant difference between campuses and pass rate, the chi-square test for association and independence should be performed.

What is the expected frequency of West Campus and failed?

21

Which of the statements about one-way ANOVA is FALSE?

22

Mike tabulated the following values for heights in inches of seven of his friends: 65, 71, 74, 61, 66, 70, and 72. The sample standard deviation is 4.577.

Select the 95% confidence interval for Mike's set of data.

23

Adam tabulated the values for the average speeds on each day of his road trip as 60.5, 63.2, 54.7, 51.6, 72.3, 70.7, 67.2, and 65.4 mph.  The sample standard deviation is 7.309.

Adam reads that the average speed that cars drive on the highway is 65 mph.

The t-test statistic for a two-sided test would be __________.  Answer choices are rounded to the hundredths place.

24

The table below shows the results of a customer satisfaction survey at a particular restaurant broken down by males and females.

 Male Female Extremely Satisfied 25 7 Satisfied 21 13 Neutral 13 16 Dissatisfied 9 14 Extremely Dissatisfied 2 5

Assuming all 5 choices are equally likely, select the observed and expected frequency for male customers that are dissatisfied.