Exam 3: Univariate Population Parameters and Sample Statistics

Without doing any computations, which of the following distributions has the largest variance? X f Y f Z f 30 3 41 2 45 3 36 2 42 4 46 1 40 3 44 2 48 1 41 2 45 4 51 3 48 2 51 2 53 3 50 3 52 2 55 3 52 2 53 2 59 3 60 3 54 2 60 3

Recall the conceptual formula for calculating the variance. Squaring the deviations from the mean in the numerator means that a negative variance will never be a possibility.

A student services employee advises 50 undergraduate students. For each student, she records the "type of student" for which they classify: a) traditional; b) non-traditional. She computes the standard deviation for "type of student." Is this appropriate given the measurement scale of this variable?

A research scientist at Disneyworld randomly samples 1,000 annual pass holders and collects data on the number of days they visited a Disney park using their annual pass during the past calendar year. The average number of days attended was 14. Which measure of central tendency does this statement represent?

The lowest number of credit hours enrolled by graduate students is one. The highest number of credit hours enrolled is 15. The difference between these values is 14. Which measure of variability does this statement represent?

Without doing any computations, which of the following distributions has the largest variance? X f Y f Z f 64 1 50 2 80 3 66 1 60 2 81 2 69 5 75 2 82 2 74 2 80 2 83 2 76 1 85 6 84 2 78 4 90 2 85 4 79 1 95 2 86 2 80 5 100 2 87 3

Of data collected on 50 schools, you are provided the number of students enrolled at the school that has the largest enrollment and the school that has the smallest enrollment. Which of the following can you calculate based on the data you have?

Without doing any computations, which of the following distributions has the largest variance? X f Y f Z f 100 1 110 5 99 1 111 4 112 1 120 4 115 1 114 2 125 4 120 1 117 2 127 4 122 4 118 2 130 2 125 1 125 1 132 3 130 1 128 1 135 1 135 7 129 6 175 1

A speech language pathologist records the number of times that children stutter during a 10 minute conversation. In her sample of 15 children, the number of times stuttered ranges from 0 to 21. The speech language pathologist computes the standard deviation on the "number of times stuttered." Is this appropriate given the measurement scale of this variable?

Monthly donations to 1,000 regional animal shelters around the country are tracked by the national animal association. You are provided with the value of the highest donation and the value of the lowest donation and are asked to generate a measure of variability on the data. Which of the following measures of variability can be generated given this data?

A research scientist at Disneyworld randomly samples 1,000 annual pass holders and collects data on the number of days they visited a Disney park using their annual pass during the past calendar year. The most frequently number of days attended was 12. Which measure of central tendency does this statement represent?

For the following data, and assuming an interval width of 1, compute the following: a. Mode b. Median c. Mean d. Exclusive and inclusive range e. H spread f. Variance and standard deviation x 25 21 16 18 19 21 21 22 17 19

The average number of credit hours enrolled by graduate students during the fall semester is nine. Which measure of central tendency does this statement represent?

An admissions counselor is conducting research on graduating college seniors. One of his survey items asks seniors to indicate what they will be doing during the month immediately following graduation. The categories include: a) working full or part-time; b) preparing for graduate school; c) seeking employment. Which measure of central tendency is appropriate to calculate given the measurement scale of this variable?

Fifty percent of college faculty earn $50,000 or less during their first year teaching. Which measure of central tendency does this statement represent?

For the following data, and assuming an interval width of 1, compute the following using SPSS: a. Mode b. Median c. Mean d. Exclusive range e. Standard deviation f. Variance X 15000 15000 15000 15000 15000 15000 15000 25000 25000 25000 25000 25000 42000 42000 45000 45000 50000 50000 65000 70000

Fifty percent of all graduate students enroll in nine or fewer credit hours during the fall semester. Which measure of central tendency does this statement represent?

The UCF athletic office has asked you to generate statistics from data collected on attendance at home football games. They have provided you two scores: the highest attended game and the lowest attended game. Which of the following can you calculate based on the data you have?

A chef at the Grand Floridian has been asked to categorize the dishes that he makes into the following: a) appetizers; b) side dishes; c) entrees; d) desserts. Which measure of central tendency is appropriate to calculate given the measurement scale of this variable?

A research scientist at Disneyworld randomly samples 1,000 annual pass holders and collects data on the number of days they visited a Disney park using their annual pass during the past calendar year. Fifty percent of all visitors attended 21 or fewer day. Which measure of central tendency does this statement represent?