22: Descriptive Students Flashcards
All of the following are methods of graphic presentation of distributions of data except:
a. Frequency distribution
b. Histogram
c. Line plot
d. Stem-and-leaf plot
a
The age in years of the individuals in a group is as follows: 11,22,24,26,13,18,16,19,30,25,16. What is the mean age in this group?
a. 11 years
b. 16 years
c. 19 years
d. 20 years
d
The ages in years of the individuals in a group is as follows: 11, 22, 24, 26, 13, 18, 16, 19, 30, 25, 16. What is the median age in this group?
a. 11 years
b. 16 years
c. 19 years
d. 20 years
c
In this distribution of ages, 11, 22, 24, 26, 13, 18, 16, 19, 30, 25, 16, what is the mode?
a. 11 years
b. 16 years
c. 19 years
d. 20 years
b
An ordinal outcome measure is reported in a study. What is the preferred measure of central tendency to report for this outcome measure?
a. Mean
b. Median
c. Mode
d. Standard deviation
b
in a positively skewed distribution, which of the following best describes the relationship between the measures of central tendency?
a. The mean is greater than the median
b. The mean is equal to the median
c. The mean is smaller than the mode
d. The mean is greater than the mode
c
The value of a sample mean is 85 and the standard deviation is 10. Assuming a normal distribution what percentage of scores will fall between 75 and 95?
a. 34%
b. 47%
c. 68%
d. 95%
c
The value of a sample mean is 75 on a midterm examination and the standard deviation is 10. What is the z-score for a student who achieves a grade of 95?
a. 1.0
b. 2.0
c. 7.5
d. 10
b
The value of a sample mean is 70 with a standard deviation is 10. What proportion of the sample has a score greater than 80?
a. 13.59%
b. 34.13%
c. 68.26%
d. 84.14%
c
Which of the following is true about the calculation of sample variance?
a. The sum of squares is not influenced by sample size
b. The sum of squares is equal to zero for a normal distribution
c. The sum of squares is divided by the sample size minus one
d. The value for the sample variance is equal to the value of the population variance
c
For ordinal data what is the preferred measure of variability?
a. Interquartile range
b. Range
c. Standard deviation
d. Variance
a
A student receives a score of 82 on a standardized exam that has a mean of 77 and a standard deviation of 10. At what percentile does the student fall?
a. 50th percentile
b. 19th percentile
c. 82nd percentile
d. 69th percentile
d
The interquartile range is:
a. The difference between the smallest and largest values
b. The difference between the first and third quartiles
c. The 50th percentile
d. Equal to the variance
b
The sum of squares in a distribution is obtained by:
a. Squaring each value in the distribution and taking the sum.
b. Subtracting the mean from each score and taking the sum of those deviation
scores.
c. Squaring the deviation scores and taking their sum.
d. Squaring the mean.
c
The standard deviation is more useful as a descriptive measure than the variance in a distribution because:
a. The standard deviation is in the same units as the original data.
b. The variance is influenced by sample size.
c. The variance is larger than the standard deviation.
d. Variance is a population parameter.
a
