Deck 5: Measures of Dispersion

Question 1

The standard deviation is called that because it represents a "standard" approach to measuring variation.

Answer 1

False

Question 2

Using the total distance between all scores and their mean produces

A)a large degree of variance that must be minimized by taking the square root of the result
B)the concept of total score distance,which is then used in sophisticated statistics
C)the minimum possible amount of total dispersion created by a differencing technique
D)the concept of mean distance,which is then used in sophisticated statistics

Answer 2

C

Question 3

If you wanted to express the variation or dispersion of a group in its original measurement terms,you would use the variance statistic.

Answer 3

False

Question 4

Perfect heterogeneity is a relative concept.

Question 5

The general concept of dispersion or variation is represented best by which item below?

A)the degree of movement in a data distribution away from the extremes
B)any measure of difference between one set of scores and another
C)the amount of spread in a data distribution
D)an estimation of the degree of error in using any one score as the homogeneous center of a distribution

Question 6

Measures of dispersion

A)represent a measure of distance along a score distribution
B)cannot be used to describe a group
C)describe a central point on a score distribution
D)none of the above

Question 7

Which of the following is the average squared distance of each score from its mean?

A)variance
B)error
C)standard deviation
D)average deviation

Question 8

A score of zero represents which concept below?

A)the standard deviation if you remove the square root sign
B)an absolute
C)extremes
D)homogeneity

Question 9

What is the relationship between the variance statistic and the standard deviation statistic?

A)the variance is always twice the size of the standard deviation
B)the standard deviation is the variance divided by the sample size
C)the variance is the square root of the standard deviation
D)the standard deviation is the square root of the variance

Question 10

If the scores in a distribution are close to each other,those scores are

A)homodistributed
B)heterospread
C)homogeneous
D)heterogeneous

Question 11

If the magnitude of means in two groups is substantially different,in order to compare their dispersion you would need

A)the square root of the variance
B)to square the standard deviation
C)to square the absolute deviation
D)none of the above

Question 12

Dispersion measured by using extremes is a better approach than dispersion measured by using the distance between a score and its central point.

Question 13

The range:

A)is the average of the summed medians in a group of samples
B)is affected by extreme scores (outliers)
C)is useful in many of the more advanced statistics
D)none of the above

Question 14

Perfect homogeneity occurs when

A)all scores are the same
B)all scores are different
C)scores are as far apart as possible for the scale on which they are being measured
D)none of the above,"perfect" homogeneity is impossible to achieve.

Question 15

It you measure the highest and lowest scores in a set of data and determine the distance between them,you have

A)the standard deviation
B)the range
C)the semi-interquartile distance
D)none of the above

Question 16

The standard deviation is a univariate statistic.

Question 17

If the standard deviation statistic is used,what must the level of measurement of the variable be?

A)ordinal
B)nominal
C)ratio
D)interval

Question 18

Which of these measures use an interval level measurement?

A)range
B)standard deviation
C)variance
D)all of the above

Question 19

The variance can be used with

A)interval or ratio level data
B)ordinal or nominal level data
C)ordinal or interval level data
D)nominal or ratio level data

Question 20

The expression (x - )in a statistical formula can be called:

A)a diminishing technique
B)a mathematical correction
C)a distancing technique or a deviation score
D)standardization

Question 21

The coefficient of relative variation is a measure that controls for the magnitude of group means when the standard deviation is used to compare groups.

Question 22

If you are measuring the spread of data in a distribution,it is best to use the median in all formulas to avoid having a problem with extremes.

Question 23

The number of scores can have a greater effect on the size of a dispersion value than the actual spread in the data.

Question 24

The standard deviation can be used to compare the amount of dispersion in any two groups regardless of the size of their respective means.

Question 25

The concept of distance can be something so simple as subtracting a group mean from any of its scores.