Exam 2: Organizing and Visualizing Variables

SCENARIO 2-6 A sample of 200 students at a Big-Ten university was taken after the midterm to ask them whether they went bar hopping the weekend before the midterm or spent the weekend studying, and whether they did well or poorly on the midterm.The following table contains the result. Did Well in Midterm Did Poorly in Midterm Studying for Exam 80 20 Went Bar Hopping 30 70 -Referring to Scenario 2-6, of those who did well on the midterm in the sample, percent of them went bar hopping the weekend before the midterm.

Which of the following is appropriate for displaying data collected on the different brands of cars students at a major university drive?

SCENARIO 2-8 The Stem-and-Leaf display represents the number of times in a year that a random sample of 100 "lifetime" members of a health club actually visited the facility. Stem Leaves 0 01222223333334445666666667789999 1 1111222234444555669999 2 00011223455556889 3 0000446799 4 011345567 5 0077 6 8 7 67 8 3 9 0247 -Referring to Scenario 2-8, the person who visited the health club less than anyone else in the sample visited the facility times.

SCENARIO 2-12 The table below contains the opinions of a sample of 200 people broken down by gender about the latest congressional plan to eliminate anti-trust exemptions for professional baseball. For Neutral Against Totals Female 38 54 12 104 Male 12 36 48 96 Totals 50 90 60 200 -Referring to Scenario 2-12, if the sample is a good representation of the population, we can expect percent of those for the plan in the population will be males.

SCENARIO 2-7 The Stem-and-Leaf display below contains data on the number of months between the date a civil suit is filed and when the case is actually adjudicated for 50 cases heard in superior court.Stem Leaves 1 234447899 2 22223455678889 3 0011135778 4 02345579 5 112466 6 158 -Referring to Scenario 2-7, the civil suit with the longest wait between when the suit was filed and when it was adjudicated had a wait of months.

SCENARIO 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. Time(inMinutes) Relative Frequency 0 but less than 5 0.37 5 but less than 10 0.22 10 but less than 15 0.15 15 but less than 20 0.10 20 but less than 25 0.07 25 but less than 30 0.07 30 or more 0.02 -Referring to Scenario 2-5, if 100 calls were sampled, of them would have lasted 20 minutes or more.

SCENARIO 2-11 The ordered array below resulted from selecting a sample of 25 batches of 500 computer chips and determining how many in each batch were defective. Defects 1 2 4 4 5 5 6 7 9 9 12 12 15 17 20 21 23 23 25 26 27 27 28 29 29 -Referring to Scenario 2-11, construct a cumulative percentage polygon for the defects data if the corresponding frequency distribution uses "0 but less than 5" as the first class.

SCENARIO 2-11 The ordered array below resulted from selecting a sample of 25 batches of 500 computer chips and determining how many in each batch were defective. Defects 1 2 4 4 5 5 6 7 9 9 12 12 15 17 20 21 23 23 25 26 27 27 28 29 29 -Referring to Scenario 2-11, construct a histogram for the defects data, using "0 but less than 5" as the first class.

SCENARIO 2-14 The table below contains the number of people who own a portable Blu-ray player in a sample of 600 broken down by gender. Own a Portable Blu-ray player Male Female Yes 96 40 No 224 240 -Referring to Scenario 2-14, if the sample is a good representation of the population, we can expect percent of those who own a portable Blu-ray player in the population will be males.

To compare one large set of numerical data to another, a distribution must be developed from the frequency distribution.

The percentage polygon is formed by having the lower boundary of each class represent the data in that class and then connecting the sequence of lower boundaries at their respective class percentages.

The width of each class grouping or interval in a frequency distribution should be _.

2-2 Organizing and Visualizing Variables At a meeting of information systems officers for regional offices of a national company, a survey was taken to determine the number of employees the officers supervise in the operation of their departments, where X is the number of employees overseen by each information systems officer. X f 1 7 2 5 3 11 4 8 5 9 -Referring to Scenario 2-2, across all the regional offices, how many total employees were supervised by those surveyed?

A multidimensional contingency table allows you to tally the responses of more than two continuous variables.

In determining the class interval width, is the denominator in the formula.

SCENARIO 2-12 The table below contains the opinions of a sample of 200 people broken down by gender about the latest congressional plan to eliminate anti-trust exemptions for professional baseball. For Neutral Against Totals Female 38 54 12 104 Male 12 36 48 96 Totals 50 90 60 200 -Referring to Scenario 2-12, construct a table of column percentages.

SCENARIO 2-18 The stem-and-leaf display below shows the result of a survey on 50 students on their satisfaction with their school with the higher scores represent higher level of satisfaction. -Referring to Scenario 2-18, what was the lowest level of satisfaction?

SCENARIO 2-17 The following table presents total retail sales in millions of dollars for the leading apparel companies over a two-year period in the past. APPAREL COMPANY Year 1 Year 2 Gap 1,159.0 962.0 TJX 781.7 899.0 Limited 596.5 620.4 Kohl's 544.9 678.9 Nordstrom 402.6 418.3 Talbots 139.9 130.1 Ann Taylor 114.2 124.8 -Referring to Scenario 2-17, construct a table of column percentages.

SCENARIO 2-11 The ordered array below resulted from selecting a sample of 25 batches of 500 computer chips and determining how many in each batch were defective. Defects 1 2 4 4 5 5 6 7 9 9 12 12 15 17 20 21 23 23 25 26 27 27 28 29 29 -Referring to Scenario 2-11, if a frequency distribution for the defects data is constructed, using "0 but less than 5" as the first class, the frequency of the "20 but less than 25" class would be_.

SCENARIO 2-4 A survey was conducted to determine how people rated the quality of programming available on television.Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality).The stem-and-leaf display of the data is shown below. Stem Leaves 3 24 4 03478999 5 0112345 6 12566 7 01 8 9 2 -Referring to Scenario 2-4, what percentage of the respondents rated overall television quality with a rating from 50 through 75?