Exam 2: Organizing Data

Given the following "data scenario," decide which type of grouping (single-value, limit, or cutpoint) is probably the best. -Wingspan of Cardinal: The wingspan lengths, to the nearest hundredth of a millimeter, of a sample of 35 cardinals.

A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogramfor the systolic blood pressure readings for those people aged between 25 and 40. Use the histogram to answer thequestion. The blood pressure readings were given to the nearest whole number. -Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading greater than or equal to 130?

The following table shows the average weight of offensive linemen for each given football team. Team Average weight (pounds) Gators 303.52 Lakers 326.78 Eagles 290.61 Pioneers 321.96 Lions 297.35 Mustangs 302.49 Rams 345.88 Buffalos 329.24 Identify the variable under consideration in the second column?

For a given data set, why might a researcher prefer to study organized data rather than the original data? Can you think of any circumstances in which a researcher may prefer to use the original data rather than organized data?

The lengths (in inches)of a random sample of bottlenose dolphins are given below. Truncate each observation by dropping the decimal part, then construct a stem-and-leaf diagram of the truncated Data using two lines per stem. 97.7 142.2 105.2 110.5 115.8 112.4 136.7 99.9 101.2 124.3 121.9 98.8 121.8 132.7 128.9 117.8 141.9 108.2 118.0 127.3 133.4 116.9 104.4 132.0

Suppose that you want to construct a pie chart to represent the following data. Blood Type Frequency 90 84 18 8 Explain how you would calculate the angle for the pie-shaped piece corresponding to the blood type O.

Construct a dotplot for the given data. -The following data represent the number of cars passing through a toll booth during a certain time period over a number of days. $181917172418211819152219231721$

Attendance records at a school show the number of days each student was absent during the year. The days absent for each student were as follows. $934286340673422$

Use single-value grouping to organize these data into a frequency distribution. -The following data represent the total number of years of formal education for 40 employees of a bank. 13 17 13 14 12 17 19 13 15 13 16 18 13 11 19 19 12 14 13 13 14 15 13 15 17 18 17 14 13 17 12 17 17 16 16 17 15 13 13 14 Construct a frequency distribution for the number of years of education.

Use cutpoint grouping to organize these data into a frequency distribution. -On a math test, the scores of 24 students were 93 72 71 62 71 71 93 87 71 61 85 72 72 85 71 72 85 71 72 87 72 85 87 62 Construct a frequency distribution. Use 4 classes beginning with a lower class limit of 60 . Score Frequency

Given the following "data scenario," decide which type of grouping (single-value, limit, or cutpoint) is probably the best. -Exam Scores: The exam scores, rounded to the nearest whole number, of all students in a given math course.

Construct the requested graph. -The table lists the winners of the State Tennis Tournament women's singles title for the years 1986-2005. Construct a bar graph for the given relative frequencies. Winner Frequency Relative frequency C. Evert 2 0.10 V. Wade 1 0.05 M. Navratilova 9 0.45 C. Martinez 1 0.05 S. Graf 6 0.30 E. Goolagong 1 0.05

Provide an appropriate response. -The heights of adult women have a bell-shaped distribution. Give examples of three other data sets whose distributions are likely to be bell-shaped.

Hospital records show the age at death of patients who die while in the hospital. A frequency histogram is constructed for the age at death of the people who have died at the hospital in the past five years. Roughly what shape would you expect for the distribution? Why?

500 movie critics rated a movie. The following data give the rating distribution. Rating Frequency Relative Frequency Excellent 100 0.20 Good 250 0.50 Fair 150 0.30

The table contains the frequency and relative-frequency distributions for the ages of the employees in a particular company department. Age (years) Frequency Relative frequency 20 -under 30 3 0.1875 30 -under 40 6 0.375 40 -under 50 4 0.25 50 -under 60 1 0.0625 60 -under 70 2 0.125

A graphical display of a data set is given. State whether the distribution is (roughly)symmetric, right skewed, or leftskewed. -A stem-and-leaf diagram is given below for the annual precipitation in one U.S. city for 28 consecutive years. Precipitation data are in inches. 0 9 1 142 2 0203 3 01472832 4 13487 5 1748 6 36 7 1

The data in the following table reflect the amount of time 40 students in a section of Statistics 101 spend on homework each day. Determine the value that should be entered in the relative frequency Column for the class 0-14. Homework time (minutes) Number of students Relative frequency 0-14 2 15-29 4 30-44 10 45-59 16 60-74 6 75-89 2

Provide an appropriate response. -A population has a J-shaped distribution. Two different samples of size 12 are picked from the population. Two different samples of size 1000 are then picked from the population. Do you think that the distribution of the two samples of size 12 will have roughly the same shape? Do you think that the distribution of the two samples of size 1000 will have roughly the same shape? Explain your thinking.

Complete the contingency table and use it to solve the problem. -The partially filled contingency table gives the relative frequencies of the data on age (in years)and sex from the residents of a retirement home. What percentage of residents are males over 79 ?