Deck 3: Descriptive Statistics, Probability, and Measures of Central Tendency

Question 1

Researchers examined the relationship between interpersonal violence and health in college age women. The researchers administered a psychological distress questionnaire which produced a score on a scale of 0-12. What would be an appropriate measure of central tendency to consider for this variable?

A) Mean
B) Median
C) Mode
D) Any of these measures of central tendency would be appropriate.

Answer 1

D

Question 2

A researcher collects demographic data on the marital status of the study subjects. The variable is measured as married/not married. What would be the most appropriate measure of central tendency?

A) Mean
B) Median
C) Mode
D) Any of these measures of central tendency would be appropriate.

Answer 2

C

Question 3

A researcher collects demographic data on the marital status of the study subjects. The variable is measured as married/divorced/separated/widowed/never married/cohabitating. What would be the most appropriate measure of central tendency?

A) Mean
B) Median
C) Mode
D) Any of these measures of central tendency would be appropriate.

Answer 3

C

Question 4

A researcher collects demographic data on the marital status of the study subjects. The variable is measured as the number of years married on a scale of 0-75. What would be the most appropriate measure of central tendency?

A) Mean
B) Median
C) Mode
D) Any of these measures of central tendency would be appropriate.

Question 5

A researcher collects demographic data on the marital status of the study subjects. The variable is measured as married <2 years, married 2-9 years, married >9 years. The researcher reports that the most frequent response from subjects is married <2 years. What other measure of central tendency would be appropriate to report from this type of variable?

A) Mean
B) Median
C) Mode
D) Any of these measures of central tendency would be appropriate.

Question 6

Your subjects complete a pretest to assess their cognitive skills and have a median score of 67% on the pretest. Then they complete your intervention and a post-test with the following scores: 82%, 79%, 47%, 65%, 81%, 57%, 57%, 52% and 66%. What was the median on the posttest?

A) 67%
B) 65%
C) 57%
D) 62%

Question 7

Your subjects complete a pretest to assess their cognitive skills and have a mean score of 62% on the pretest. Then they complete your intervention and a post-test with the following scores: 82%, 79%, 47%, 65%, 81%, 57%, 57%, 52% and 76%. What was the mean on the posttest?

A) 67%
B) 65%
C) 66%
D) Unable to determine with the given information

Question 8

You have collected data about the fasting blood glucose (FBG) level of participants in your study. You are delighted to find that the variable is normally distributed. If the mean FBG is 82 and the standard deviation is 2.8 in what range would you expect to find the FBG of 68% of your study participants?

A) 79.2-84.8
B) 76.4-87.6
C) 73.6-90.4
D) Unable to determine
G) level of participants in your study. You are delighted to find that the variable is normally distributed. If the mean FBG is 82 and the standard deviation is 2.8 in what range would you expect to find the FBG of 68% of your study participants?

Question 9

You have collected data about the fasting blood glucose (FBG)level of participants in your study. You are delighted to find that the variable is normally distributed. If the mean FBG is 82 and the standard deviation is 2.8 in what range would you expect to find the FBG of 95% of your study participants?

A) 79.2-84.8
B) 76.4-87.6
C) 73.6-90.4
D) Unable to determine
G)level of participants in your study. You are delighted to find that the variable is normally distributed. If the mean FBG is 82 and the standard deviation is 2.8 in what range would you expect to find the FBG of 95% of your study participants?

Question 10

You have collected data about the average response time of participants in your study. You are delighted to find that the variable is normally distributed. If the mean response time is 12 seconds and the standard deviation is 4 seconds what percent of your subjects would you expect to respond in 4-20 seconds?

A) 50%
B) 68%
C) 95%
D) Unable to determine

Question 11

You have collected data about the average response time of participants in your study. You are delighted to find that the variable is normally distributed. The mean response time is 30 seconds and the standard deviation is 4 seconds what percent of your subjects would you expect to respond in 26-34 seconds?

A) 50%
B) 68%
C) 95%
D) Unable to determine

Question 12

You have collected data about the average age of participants in your study. You are delighted to find that the variable is normally distributed. If the mean age is 12 years and the standard deviation is 4 years. What is the median age for your subjects?

A) 12 years
B) Greater than 12 years
C) 8-16 years
D) Unable to determine

Question 13

You have collected data about the average response time of participants in your study. You are delighted to find that the variable is normally distributed. More than half your respondents take longer than 16 seconds to respond and one third take less than 12 seconds to respond. What is the median response time of your participants?

A) The same as the mean response time
B) Greater than 16 seconds
C) 16 seconds
D) Unable to determine

Question 14

You have collected data about the average response time of participants in your study. You are delighted to find that the variable is normally distributed. More than half your respondents take longer than 16 seconds to respond and one third take less than 12 seconds to respond. What is the median response time of your participants?

A) Greater than 16 seconds
B) 16 seconds
C) 12 seconds
D) Unable to determine

Question 15

You have collected data about the post void residuals (PVR) of participants in your study. The mean PVR is 120 mls. Because you have some outliers noted in your study you also report a median PVR which is 138 mls. Based on this data you know:

A) The outliers lie in equal amounts on both sides of the distribution
B) The variable is not normally distributed
C) There is a bimodal distribution
D) The researcher is biased

Question 16

Patients on your unit complete a functional mobility test. The test determines how many seconds it takes to walk 20 feet unassisted. Your patient's speed is reported as a Z score of 2.3. You would expect your patient to walk 20 feet unassisted:

A) Faster than the average patient on the unit
B) Slower than the average patient on the unit
C) 2.3 times faster than the slowest patient on the unit
D) Unable to determine

Question 17

Patients on your unit complete a functional mobility test. The test determines how many seconds it takes to walk 20 feet unassisted. Your patient's speed is reported as a Z score of -0.09. You would expect your patient to walk 20 feet unassisted:

A) Faster than the average patient on the unit
B) Slower than the average patient on the unit
C) 2.3 times faster than the slowest patient on the unit
D) Unable to determine

Question 18

Patients on your unit complete functional mobility tests. Your patient's speed is reported as a Z score of 2.3. Her strength is reported as a Z score of -0.8 You know this means:

A) Your patient's speed is better than her strength
B) Your patient is faster than 99% of the patients on the unit
C) Your patient is 2.3 times faster than the slowest patient on the unit and 0.8 times slower than the weakest patient
D) Your patient is faster than average but weaker than the average patient on the unit.

Question 19

Patients on your unit complete a functional mobility test. The test determines how many seconds it takes to walk 20 feet unassisted. Your patient's speed is reported as a Z score of 2.3. Her roommate's speed is reported as a Z score of 1.8. You would expect your patient to walk 20 feet unassisted:

A) Faster than her roommate
B) Slower than her roommate
C) 2.3 times faster than the slowest patient on the unit
D) Unable to determine

Question 20

Your unit completes the internal controls module at your workplace. Two of the nurses on your unit were internal control specialists in their last place of employment and scored a perfect score on the exam while the rest of the nurses had an average score of 78 with a range of 72-84 on the test. When you look at the grade distribution you are not surprised to see:

A) A normal distribution
B) A negative skew
C) A positive skew
D) The mean, median and mode are equal