Module 1 HMWK 1 Question 1 1 out of 1 points

What scale of measurement would you use when collecting data to represent the average monthly temperature for the city of Fort Wayne?Answer

Selected Answer: Interval

Response Feedback:That'scorrect! Since temperature has no true zero point, it is interval data.

Question 2 1 out of 1 points

What scale of measurement would you use to classify the voters in Fort Wayne as Democrat, Republican, Independent, or Undecided?Answer

Selected Answer:Nominal

Response Feedback:That'scorrect! Since there is no order to the data and it is qualitative, the data is nominal.

Question 3 1 out of 1 points

You have collected data in a survey which asks people their age. What scale of measurement applies to age?Answer

Selected Answer:Ratio

Response Feedback:That'scorrect! Age has a true zero point and is ratio data.

Question 4 1 out of 1 points

A survey has asked people to list the state where they live. What scale of measurement describes this type of data?Answer

Selected Answer:Nominal

Response Feedback:That'scorrect! Since there is no implied order of the 50 states, it is nominal data.

Question 5 1 out of 1 points

An employee appraisal form lists performance ratings as "eceeds expectations","mets expectations",and "blow expectations." hat type of measurement scale describes this type of data?Answer

Selected Answer:Ordinal

Response Feedback:That'scorrect! There is an order to the data but it is categorical in nature.

Question 6 0 out of 1 points

An analysis of the number of phone calls per day for last month is shown in the following frequency table.Calls per day Number of Days0 - 123 - 86 - 59 - 1 312 or more 2What is the relative frequency for the category 0 - ?Answer

Selected Answer:0.67

Response Feedback:That is not correct. The relative frequency is computed as the frequency divided by the total sample size.

Question 7 1 out of 1 points

The phone call data is repeated for this question.Calls per day Number of days0 - 123 - 86 - 59 - 1 312 or more 2What percent of the data falls between 2 and 9 (not including 2 and 9) calls per day?Answer

Selected Answer:0.43

Response Feedback:That'scorrect! "Btween" and 9 does not include 2 or 9. (8+5)/(12+8+5+3+2) = 13/30 = 0.43

Question 8 1 out of 1 points

You have collected data on the number of defects per 100 parts produced by a machine every hour for a twelve-hour shift. What'sthe best way to show the data graphically?Answer

Selected Answer:Time plot

Response Feedback:That'scorrect! We'v collected data over time so the time plot is best.

Question 9 1 out of 1 points

The following set {2-door, 4-door, SUV, convertible, Ford} describes cars. Which choice best describes the set?Answer

Selected Answer:Neither mutually exclusive nor collectively exhaustive

Response Feedback:That'scorrect! A car could fit into more than one category and the set does not describe all types of cars.

Question 10 1 out of 1 points

The following set {male, female} describes gender data from a survey. Which best describes the data set?Answer

Selected Answer:Both mutually exclusive and collectively exhaustive

Response Feedback:That'scorrect! A person can only fit into one category and the two together describe all people.

Saturday, April 13, 2013 12:03:28 PM EDT

Module 1 HMWK 2 Question 1 1 out of 1 points

Whats the mean of 3, 10, 5?Answer

Selected Answer: 6

Response Feedback:Mean is average. So you just do (3 + 10 + 5)/3

Question 2 1 out of 1 points

Which one of the following type of graph will be BEST to show the growth of enrollment in Indiana Tech over the past 10 years.Answer

Selected Answer:Bar graph

Question 3 1 out of 1 points

When you use your regression line to predict values that are not in the sample, and discovered large residual value in each prediction, what can you say about your regression line?Answer

Selected Answer:Large residual values indicate the prediction is way off from actual value. We will need to restudy how we did our analysis and see whether there are any lurking variables that we have not yet considered.

Question 4 1 out of 1 points

You have calculated the variance of a data set and it turns out to be zero. What conclusion can you draw?Answer

Selected Answer:All of the data points have the same value.

Response Feedback:That is correct. If the variance or standard deviation is zero, then the data points are all the same.

Question 5 1 out of 1 points

You received a voice mail from someone on a cell phone. They gave you the following numbers, 2, 3, 5, 3, 7, 8, and X. There was static on the line and you didn'thear the last number. Without know the last number, what can we say about the median of the numbers?Answer

Selected Answer:It must be between 2 and 8.

Response Feedback:That is correct. The final number can not change the fact that the median will fall between the lowest and highest number on the list.

Question 6 1 out of 1 points

If the last number was 4, what is the mode of the data set?Answer

Selected Answer:3

Response Feedback:That is correct. The mode is the value of the data point that occurs most often.

Question 7 1 out of 1 points

If the last number was 4, what is the variance of the data set?Answer

Selected Answer:4 80

Question 10 2 out of 2 points

The level of significance in hypothesis testing is the probability ofAnswer

Selected Answer:c. rejecting a true null hypothesis

Question 11 0 out of 3 points

A student believes that the average grade of the final exam in statistics is at least 85. She plans to take a sample to test this belief. The correct set of hypotheses isAnswer

Selected Answer:b. H(0): 85 H(1): < 85

Question 12 2 out of 2 points

As the sample size increases, the width of the confidence interval,Answer

Selected Answer:a. decreases

Question 13 4 out of 4 points

Men WomenSample size 64 36Salary ($1,000) 44 41Pop Variance 128 72What is the standard error for the difference between the two means?Answer

Selected Answer:b. 2.00

Question 14 4 out of 4 points

Male Female Sample Size 64 36 Sample Mean Salary (in $1,000) 44 41 Population Variance 128 72What is the half-width of the 95% confidence interval?Answer

Selected Answer:d. 3.92

Question 15 4 out of 4 points

Male Female Sample Size 64 36 Sample Mean Salary (in $1,000) 44 41 Population Variance 128 72What is the 95% confidence interval for the difference between the two means?Answer

Selected Answer:a. -0.92 X 6.92

Question 16 4 out of 4 points

Male Female Sample Size 64 36 Sample Mean Salary (in $1,000) 44 41 Population Variance 128 72You are testing the hypothesis that average salary for men is greater than for women. What is the computed test statistic?Answer

Selected Answer:b. 1.50

Question 17 4 out of 4 points

Male Female Sample Size 64 36 Sample Mean Salary (in $1,000) 44 41 Population Variance 128 72What is the p-value for testing the hypothesis that average salary for men is greater than for women? The level of significance is 0.95.Answer

Selected Answer:b. 0.0668

Question 18 0 out of 4 points

MaleFemaleSample Size6436Sample Mean Salary (in $1,000)4441Population Variance12872For a 95% confidence, what conclusion can you draw about average salaries?Answer

Selected Answer:d. None of the above are true.

Question 19 2 out of 2 points

When s is used to estimate , the confidence interval is computed using theAnswer

Selected Answer:d. t distribution

Question 20 0 out of 3 points

The school's newspaper reported that the proportion of students majoring in business is more than 30%. You plan on taking a sample to test the newspaper's claim. The correct set of hypotheses isAnswer

Selected Answer:b. H(0): p 0.3 H(1): p < 0.3

Question 21 3 out of 3 points

You have a deck of cards (54 cards, including the jokers). What's the probability of pulling 4 aces in a row? (Once you take a card out, you don't put it back).Answer

Selected Answer:c. 1/54 * 1/53 * 1/52 * 1/51

Question 22 4 out of 4 points

You are hosting a lottery game. There are 1000 tickets to be sold and each will cost $1. Out of 1000 tickets, there will be one lucky winner to win $100. There will be 5 lucky winners to win $50, and 50 lucky winners to win $1. What's the expected value of $1 you will spend on buying a ticket?Answer

Selected Answer:d. 40 cents

Question 23 3 out of 3 points

When developing an interval estimate for the difference between two sample means, with sample sizes of n1 and n2, Answer

Selected Answer:d. n1and n2 can be any size

Question 24 2 out of 2 points

Independent simple random samples are taken to test the difference between the means of two populations whose variances are not known. The sample sizes are n1 = 32 and n2 = 40. The correct distribution to use is theAnswer

Selected Answer:c. t distribution with 70 degrees of freedom

Question 25 3 out of 3 points

For a one-tailed hypothesis test (upper tail) the p-value is computed to be 0.034. If the test is being conducted at 95% confidence, the null hypothesisAnswer

Selected Answer:d. is rejected

Question 26 3 out of 3 points

In order to determine whether or not a particular medication was effective in curing the common cold, one group of patients was given the medication, while another group received sugar pills. The results of the study are shown below. Patients Cured Patients Not Cured Received medication65 10 Received sugar pills 20 55The expected frequency for those who received medication and were cured isAnswer

Selected Answer:c. 42.5

Question 27 4 out of 4 points

In order to determine whether or not a particular medication was effective in curing the common cold, one group of patients was given the medication, while another group received sugar pills. The results of the study are shown below. Patients Cured Patients Not Cured Received medication 65 10 Received sugar pills 20 55What is the computed chi-square statistic to test if the medication is effective?Answer

Selected Answer:d. 54.69

Question 28 3 out of 3 points

In order to determine whether or not a particular medication was effective in curing the common cold, one group of patients was given the medication, while another group received sugar pills. The results of the study are shown below. Patients Cured Patients Not Cured Received medication 65 10 Received sugar pills 20 55What are the number of degrees of freedom associated with a hypothesis test?Answer

Selected Answer:a. 1

Question 29 4 out of 4 points

You have two dice in your hand. When you roll both dice, is the probability of getting an 8 (the sum of the two, like the first one 3 and second one 5) the same as getting a 3?Answer

Selected Answer: False

Question 30 4 out of 4 points

You have a die and a coin. You toss the coin and roll the die. Is the probably of getting a Head and a 3, the same as the probability of getting a Tail and a 5?Answer

Selected Answer: True

Question 31 0 out of 3 points

You are interested in finding out whether mortgage interest rate has any relationship with home sales. After reviewing home sales for the past 20 years at different mortgage rates, you saw a correlation value of -3. What can you say about your study?Answer : CORRECT ANSWER: Selected Answer: There must be an error in the calculation as correlation values cannot be -3.

Selected Answer: There is a negative correlation. When mortgage rate went up, home sales went down and vice versa.

Question 32 2 out of 2 points

An experiment is the same as an observational study since in an eexperiment you typically have to observe the responses from all participating subjects.Answer

Selected Answer: False

Question 33 3 out of 3 points

Consider the following set of numbers:

1, 10, 2, 8, 4

What's the median?Answer

Selected Answer: 4

Question 34 3 out of 3 points

Consider the following set of numbers:

1, 10, 2, 8, 4

What's the mean?Answer

Selected Answer: 5

Question 35 2 out of 2 points

Area under a density curve is always: Answer

Selected Answer: 1