class 7 Flashcards
The statement “the percentage of cases scored below a given score” refers to:
a. Quartiles
b. Percentile
c. range
d. None of the above
b
Mathematically, the standard deviation could be defined as:
a. The average of the sum of the absolute values of deviations around the mean
b. The average of the square root of the sum of the deviations around the mean
c. The square root of the average of the sum of squared deviations around the mean
d. The squared average of the sum of scores of a distribution
c
True or false: A score is considered a potential outlier if it is greater or less than one and a half times the interquartile range.
true
A ___________ is a score below which a given percentage of cases fall.
a. percentile
b. maximum
c. range
d. standard deviation
a
The distance between the 25th and 75th percentile is known as ___________.
a. range
b. interquartile range
c. 50-th percentile
d. intermediate range
b
True or false: When all scores in a population are the same, the standard deviation will always be
equal to zero.
true
Each of the following is a characteristic of standard deviation, except:
a. The standard deviation is always positive.
b. The standard deviation is affected by the value of every score in a distribution.
c. The standard deviation is used to describe qualitative variables.
d. Standard deviations are almost always reported with the mean.
c
True or false: variability can be negative.
false
How many scores are included to compute the range?
a. Two scores; the largest and smallest score in a distribution.
b. Two scores; the 75-th and 25-th percentile.
c. Three scores, the 75-th, 50-th and 25-th percentile.
d. All the scores of a variable’s distribution.
a
Suppose you know the minimum, the maximum, and the 25-th, 50-th, and 75-th percentiles of a distribution. Which of the following descriptive statistics can you determine?
a. mean and mode
b. interquartile range and mean
c. range and standard deviation
d. range and interquartile range
d
Consider the following scores (from lowest to highest): 1, 2, 3, 4, 5, 6, 7, 8. What is the range?
a. range = 7
b. range = 8
c. range = 4.5
d. We do not have enough information to compute the range
a
When data are divided into four equal parts, the data are split into________.
a. Bins
b. Ranges of grouped data
c. Quartiles
d. Interquartile ranges
c
True or false. Sometimes, the range is smaller than the interquartile range.
false
True or false: The sum of the differences of scores from their mean is zero.
true
A description of the amount of variation in a variable is called ______.
a. average
b. dispersion
c. diffusion
d. differentiation
b