Chapter 1 Assignment
AVX Home Entertainment Incorporated recently began a "no-hassles" return policy. A sample of 505 customers who recently returned items showed 320 thought the policy was fair, 150 thought it took too long to complete the transaction, and the rest had no opinion. On the basis of this information, make an inference about customer reaction to the new policy.
Customer Reaction - Percent Fair ------------- 63.4% Too Long ------ 29.7% No Opinion ---- 6.9% The above data suggest that majority of customers believe the policy is fair.
A poll solicits a large number of college undergraduates for information on the following variables: the name of their cell phone provider (AT&T, Verizon, and so on), the numbers of minutes used last month (200, 400, for example), and their satisfaction with the service (Terrible, Adequate, Excellent, and so forth). What is the level of measurement for each of these three variables?
The cell phone provider ------------ Nominal The number of minutes used ------- Ratio Satisfaction with the service -------- Ordinal
What is the level of measurement for each of the following variables? a. Student IQ ratings. b. Distance students travel to class. c. The jersey numbers of a sorority soccer team. d. A student's state of birth. e. A student's academic class—that is, freshman, sophomore, junior, or senior. f. Number of hours students study per week.
a. Interval b. Ratio c. Nominal d. Nominal e. Ordinal f. Ratio
Exits along interstate highways were formerly numbered successively from the western or southern border of a state. However, the Department of Transportation changed most of them to agree with the numbers on the mile markers along the highway. a. What level of measurement were data on the consecutive exit numbers? b. What level of measurement are data on the milepost numbers? c. The newer system provided information on the distance between exits.
a. Ordinal b. Ratio c. True
Classify the following as a population or sample: a. All the senators of the United States presently in office. b. 1,500 people selected to find out the soft drink preference in Chicago.
a. Population b. Sample
For the following situations, would you collect information using a sample or a population? a. To find how many books are published in one week by a famous publishing company. b. To test a new drug produced by a biotech company. c. To find the number of men and women working in an IT company with 600 people. d. To estimate the average salary of doctors in California.
a. Population b. Sample c. Population d. Sample
Slate is a daily magazine on the Web. Its business activities can be described by a number of variables. What is the level of measurement for each of the following variables? a. The number of hits on their website on Saturday between 8:00 a.m. and 9:00 a.m. b. The departments, such as food and drink, politics, foreign policy, sports, etc. c. The number of weekly hits on the Sam's Club ad. d. The number of years each employee has been employed with Slate.
a. Ratio b. Nominal c. Ratio d. Ratio
MarkLines is an online portal (www.marklines.com) that reports automotive industry data. The table below shows the number of cars sold in the United States in 2018 and 2019. The top 22 manufacturers, plus others, are listed here. Sales data often are reported in this way to compare current sales to last year's sales. a. Using computer software, compare 2018 sales to the 2019 sales for each manufacturer by computing the difference. Make a list of the manufacturers that increased sales from 2018 to 2019; make a list of manufacturers that decreased sales. Which manufacturers are in the top five with increased sales? Which manufacturers are in the bottom five with decreased sales? b. Using computer software, compare 2018 sales to 2019 sales for each manufacturer by computing the percentage change in sales. Make a list of the manufacturers in order of increasing percentage changes. Which manufacturers are in the top five in percentage change? Which manufacturers are in the bottom five in percentage change? c-1. Using computer software, first sort the data using the 2019 year-to-date sales. Then, design a bar graph to illustrate the 2018 and 2019 year-to-date sales for the top 10 manufacturers and select the most appropriate graph below. c-2. Design a bar graph to illustrate the percentage change for the top 10 manufactiurers by 2019 year-to-date sales and select the most appropriate graph below.
a. Top Five Manufacturer - Difference 2018 to 2019 Tesla ---------- 52,800 Hyundai ------ 32,061 Kia ------------ 25,665 Subaru -------- 19,982 BMW ---------- 13,812 Bottom Five Manufacturer - Difference 2018 to 2019 FCA ----------- (-31,541) Toyota -------- (-43,325) GM ------------ (-73,610) Ford ----------- (-79,034) Nissan --------- (-148,196) b. Top Five Manufacturer - % change from 2018 Tesla --------- 41.85% Volvo -------- 10.15% Porsche ------ 7.63% Hyundai ------ 4.73% BMW --------- 4.44% Bottom Five Manufacturer - % change from 2018 Mazda -------- (-7.25%) Nissan -------- (-9.92%) Others -------- (-13.55%) MINI ---------- (-17.38%) smart --------- (-46.71%) c-1 Bar graph A c-2 Bar graph A
Explain the difference between qualitative and quantitative variables. Qualitive data is ________, whereas quantitative data is ________.
not numerical; numerical
Explain the difference between a discrete and a continuous variable. Discrete variables can assume __________, but continuous variables can assume _________ within some range.
only certain values; any values
