STAT200 week 1 homework

Week # Text Chapter Exercise page

1 1 Lane et al. 1 3 62

1 2 Lane et al. 1 10 63

1 3 Lane et al. 1 17 64

1 4 Lane et al. 1 18 64

1 5 Illowsky et al. 1 50 53

1 6 Illowsky et al. 1 52 53

1 7 Illowsky et al. 1 72 54

1 8 Illowsky et al. 1 80 56

1 9 Illowsky et al. 1 84 57

1 10 Illowsky et al. 1 90 59

Week 1 # Lane et al.

3. If you are told only that you scored in the 80th percentile, do you know from

that description exactly how it was calculated? Explain.

10. For the numbers 1, 2, 4, 16, compute the following:

?X

?X²

(?X)²

17. (AT) What is the independent variable of this experiment? How many levels

does it have? http://onlinestatbook.com/2/case_studies/adhd.html

18. (AT) What is the dependent variable? On what scale (nominal, ordinal, interval, ratio) was it measured? http://onlinestatbook.com/2/case_studies/adhd.html

Week#1 illowsky et al.

A Lake Tahoe Community College instructor is interested in the mean number of days Lake Tahoe Community College math students are absent from class during a quarter.

50.What is the population she is interested in?

a. all Lake Tahoe Community College students

b. all Lake Tahoe Community College English students

c. all Lake Tahoe Community College students in her classes

d. all Lake Tahoe Community College math students

52.The instructor’s sample produces a mean number of days absent of 3.5 days. This value is an example of a:

a. parameter.

b. data.

c. statistic.

d. variable.

72.A study was done to determine the age, number of times per week, and the duration (amount of time) of residents using a local park in San Jose. The first house in the neighborhood around the park was selected randomly and then every eighth house in the neighborhood around the park was interviewed. The sampling method was:

a. simple random

b. systematic

c. stratified

d. cluster

80.Fifty part-time students were asked how many courses they were taking this term. The (incomplete) results are shown below:

Table 1.33 Part-time Student Course Loads

b. What percent of students take exactly two courses?

c. What percent of students take one or two courses?

84.Forbes magazine published data on the best small firms in 2012. These were firms which had been publicly traded for at least a year, have a stock price of at least $5 per share, and have reported annual revenue between $5 million and $1 billion. Table 1.37shows the ages of the chief executive officers for the first 60 ranked firms.

60

a. What is the frequency for CEO ages between 54 and 65?

b. What percentage of CEOs are 65 years or older?

c. What is the relative frequency of ages under 50?

d. What is the cumulative relative frequency for CEOs younger than 55?

e. Which graph shows the relative frequency and which shows the cumulative relative frequency?

90.Seven hundred and seventy-one distance learning students at Long Beach City College responded to surveys in the 2010-11 academic year. Highlights of the summary report are listed in Table 1.39

Table 1.39

a. What percent of the students surveyed do not have a computer at home?

b. About how many students in the survey live at least 16 miles from campus?

c. If the same survey were done at Great Basin College in Elko, Nevada, do you think the percentages would be the same? Why?