Chapter 3 Quantitative Psychology
Compute the variance using the following: n = 24 and s = 1.56.
2.43
With a lowest score of 21 and a range of 47, what is your highest score?
68
When assessing variance, the individual score minus mean score provides what information?
The deviation.
The symbol S represents the standard deviation for ______.
a sample
Which of the following is not a measure of variability?
mean
When you subtract the smallest number in the distribution from the largest, what type of variability is calculated?
range
Which of the following sets of numbers has the greatest variability?
10,7,15,19,11
Calculate the variance for the following set of scores: 10, 15, 12, 18, 19, 16, 12.
11.29
What is the range of the following set of numbers: 11, 15, 23, 22,14?
12
Calculate the mean for the following set of scores: 20, 24, 26, 22, 18, 16, 18.
20.57
What is the standard deviation for the following set of scores: 10, 15, 12, 18, 19, 16, 12?
3.36
What is the standard deviation for the following set of scores: 20, 24, 26, 22, 18, 16, 18?
3.60
What is the range for the following set of scores: 26, 48, 21, 55, 37?
34
What is the inclusive range for this set of scores: 32,15,19,57,22?
43
Which of these is the correct range for the following scores? 3, 6, 2, 9, 5, 5, 9.
7
A greater standard deviation indicates less variance.
False
It is impossible for a set of data to have no variability.
False
The standard deviation is stated in units that are squared.
False
Variance is an easy number to interpret.
False
When computing variance, which of these is an accurate statement about the sum of the deviations?
It will always be zero.
Chapter 3 shows you the formula for computing standard deviation for a sample. Dr. Frey's Lightboard video showed you how to compute the standard deviation for a population. Which element of the formula is modified when computing standard deviation for the population?
The denominator (dividing by n-1)
A standard deviation of 0 indicates no variance in your data.
True
Both standard deviation and variance are measures of variability, dispersion, or spread.
True
The variance is more difficult to interpret than the standard deviation.
True
Variability is also called dispersion or spread.
True
The symbol σ represents the standard deviation for ______.
a population
When we take the absolute value of the difference scores when calculating a measure of variability, we are using the ______.
average deviation
The calculation of the average deviation differs from the calculation of the standard deviation in that the difference scores are ______.
converted to absolute values
The highest score minus the lowest score is equal to the ______.
exclusive range
When calculated on the same distribution of scores, the average deviation will be ______ the standard deviation.
less than
In order to calculate the standard deviation, what must you calculate first?
mean
In order to calculate the variance, which of the following must you know?
mean
Which measure of variability is easiest to calculate?
range
Which of the following is the simplest measure of variability to calculate?
range
What are the three tools used to assess variability? What are three most common measures of variability?
range, standard deviation, and variance
Imagine that distribution A contains the following scores: 3, 4, 5, 6, 7. Imagine that distribution B contains the following scores: 1, 3, 5, 8, 10. Distribution A has a ______ standard deviation and a ______ average deviation in comparison to distribution B.
smaller, smaller
What is another term for variability?
spread or dispersion
When computing the standard deviation, statisticians eliminate the negative numbers by _____________________.
squaring the score
What is found by taking the square root of the variance?
standard deviation
What is the most frequently used measure of variability?
standard deviation
When we square the difference scores when calculating a measure of variability, we are using the ______.
standard deviation
Which of the following represents the average amount of variability in a set of scores?
standard deviation
The difference between computing variance and standard deviation is _______________.
taking the square root of the score that results from the division step
The range is ______.
the difference between the lowest and highest scores in the distribution
The standard deviation is ______.
the square root of the average squared deviation from the mean
The symbol s represents the standard deviation for ______.
the unbiased estimator of the population standard deviation
Biased estimates can be used ______.
to describe a sample
Unbiased estimates can be used ______.
to make population estimates
The term used to describe how much scores differ from one another is ______.
variability
When reporting descriptive data such as the mean, what additional information should also be reported that expresses how different the scores are in the distribution?
variability
Which of the following measures scores differ from each other?
variability
Which of the following is calculated by squaring the standard deviation?
variance