26 Jan left parenthesis 18 comma

Week 1 Homework

Question 1

State whether each of the following variables is categorical or numerical. If? categorical, give the level of measurement. If? numerical, is it discrete or? continuous?

a. Height left parenthesis in feet comma meters comma etc. right parenthesis of a football team’s starting quarterback

b. Response to whether or not a hockey player scored a goal in the all dash star game

c. Number of e dash mail messages sent daily by a financial planner

d. Size of a vanilla chai tea left parenthesis small to extra large right parenthesis

a. Determine the classification for the height variable. Choose the correct answer below.

numerical?, continuous

categorical?, ordinal

categorical?, nominal

numerical?, discrete

b. Determine the classification for the response variable. Choose the correct answer below.

numerical?, continuous

numerical?, discrete

categorical?, nominal

categorical?, ordinal

c. Determine the classification for the number of messages variable. Choose the correct answer below.

numerical?, continuous

numerical?, discrete

categorical?, ordinal

categorical?, nominal

d. Determine the classification for the size variable. Choose the correct answer below.

categorical?, ordinal

categorical?, nominal

numerical?, continuous

numerical?, discrete

Question 2

A university administrator requested a breakdown of travel expenses for faculty to attend various professional meetings.

Expenses

?%

A. Transportation

46

B. Lodging

21

C. Food

12

D. Conference fees

5

E. Miscellaneous

16

a. Construct a pie chart.

b. Construct a bar chart.

Question 3

The accompanying data are the earnings per share of a corporation over a period of 28 years. Graph the series and comment on the plot.

Click the icon to view the earnings data.

Comment on the plot. Choose the correct answer below.

A.

The earnings per share increased fairly steadily as the years? progressed, with the occasional small jump upward.

B.

The earnings per share fluctuated? wildly, with frequent jumps up and down and no discernable trend in either direction.

C.

The earnings per share steadily decreased for the first 14? years, and then steadily increased for the second 14 years.

D.

The earnings per share increased and decreased a fair? amount, though sudden jumps up or down in consecutive years were uncommon.

Questions 4

Prepare a scatter plot of the given data.

?(66?,5353?)

?(2222?,6666?)

?(1414?,4848?)

?(1111?,6767?)

?(1010?,4545?)

?(33?,5555?)

?(77?,5353?)

?(2222?,5656?)

?(1818?,4949?)

?(1414?,6767?)

?(1010?,5353?)

?(66?,5555?)

?(88?,5353?)

?(2222?,5151?)

?(1212?,4949?)

?(1414?,5757?)

?(1010?,5959?)

?(33?,5555?)

Choose the correct graph below.

Questions 5

A supervisor of a plant kept records of the time? (in seconds) that employees needed to complete a particular task. The data are summarized below.

Time

30less than<40 40less than<50 50less than<60 60less than<80 80less than<100 100less than<120 Number 88 1616 2020 2828 2121 20 a. Graph the data with a histogram. b. Discuss possible errors. a. Which of the graphs below correctly depicts a histogram for the given data? set? b. Discuss possible errors. Select all that apply. A. A possible error is the construction of a histogram with unequal interval widths when some of the classes vary in width. B. A possible error is the construction of a histogram with equal interval widths when some of the classes actually vary in width. C. A possible error in constructing a histogram is to make the heights of the? rectangles, rather than the areas of the? rectangles, proportional to the frequencies when some of the classes vary in width. D. A possible error in constructing a histogram is to make the areas of the? rectangles, rather than the heights of the? rectangles, proportional to the frequencies when some of the classes vary in width. Questions 6 A textile manufacturer obtained a sample of 50 bolts of cloth from a? day's output. Each bolt is carefully inspected and the number of imperfections is recorded in the accompanying table. Find the? mean, median, and mode for these sample data. Number of imperfections 0 1 2 3 Number of bolts 3030 1414 44 2 The mean of the data set is The median of the data set is Select the correct choice below? and, if? necessary, fill in the answer box to complete your choice. The? mode(s) of the data set? is/are The data set has no mode. Questions 7 Calculate the mean dollar amount and the standard deviation for the dollar amounts of the population of costs listed below. 30.27????84.86????48.76????59.03????57.99????57.32????57.07????48.21????56.42????30.58 The population mean is ? The population standard deviation is Questions 8 Consider the sample of five values and corresponding weights shown to the right. x Subscript i w Subscript i 4.4 7 3.5 8 a. Calculate the arithmetic mean of the x Subscript i values without weights. 5.3 4 b. Calculate the weighted mean of the x Subscript i values. Questions 9 Consider the frequency distribution shown to the right for a sample of 40 observations. Class Frequency ?0-4 7 ?5-9 10 a. Calculate the sample mean. ?10-14 13 b. Calculate the sample variance and sample standard deviation. ?15-19 8 ?20-24 2 Question 10 The following is a random sample of eleven? (x,y) pairs. left parenthesis 15 comma 5 right parenthesis(15, 5) left parenthesis 54 comma 18 right parenthesis(54, 18) left parenthesis 21 comma 7 right parenthesis(21, 7) left parenthesis 9 comma 3 right parenthesis(9, 3) left parenthesis 54 comma 18 right parenthesis(54, 18) left parenthesis 36 comma 12 right parenthesis(36, 12) left parenthesis 18 comma 6 right parenthesis(18, 6) left parenthesis 33 comma 11 right parenthesis(33, 11) left parenthesis 57 comma 19 right parenthesis(57, 19) left parenthesis 3 comma 1 right parenthesis(3, 1) left parenthesis 39 comma 13 right parenthesis(39, 13) a. Compute the covariance. b. Compute the correlation coefficient.