Which of the following measures show how scores differ from the mean?
variability
Which of the following is not a measure of variability?
mean
measures are: range, standard deviation, variance
In order to calculate the variance, which of the following must you know?
mean
if you know the standard deviation of a set of scores you know the variance
What is another term for variability?
spread or dispersion
What are the three tools used to assess variability?
range, standard deviation, variance
Which measure of variability is easiest to calculate?
range
Which measure of variability is most general, and hence least useful?
range
Which measure of variability should never be used alone to reach conclusions regarding the variance of a distribution?
range
Which measure of variability is a measure of the average distance from the mean?
standard deviation
What is the range for the following set of scores: 29, 48, 22, 37, 55?
55-22=33
What is the range for the following set of scores: 34, 14, 17, 57, 22?
43
What is the range for the following set of scores: 117, 249, 326, 47, 442?
395
If you have a lowest score of 21 and a range of 47, your highest score will be:
68
Which of the following measures how different scores are from one particular score?
variability
What is the most common measure of variability?
standard deviation
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?
( averages and variability)
If you subtract the smallest number in the distribution from the largest, what type of variability is being calcuated?
range
In the formula for computing the range, what does the letter "h" represent?
highest score in the data set
In the formula for computing the range, what does the letter "l" represent?
lowest score in the data set
This is used to represent the range:
r
The highest score minus the lowest score is equal to:
the exclusive range r=h-l
The highest score minus the lowest score plus one is equal to
the inclusive range r=h-l+1
In the formula for calculating the standard deviation, what does the Greek letter ""sigma represent?
find the sum of what follows ( summation)
In the formula for calculating the variance, what does the letter "n" represent?
sample size
When calculating the standard deviation, what must be done in order to obtain an unbiased estimate?
subtract 1 from n n-1
Which of the following sets of scores has the greatest variability?
7,10,11,15,19
Which of the following sets of scores has the least variability?
5,4,5,6,5
Variability is a measure of how much individual scores differ from the ______________.
mean
What is the formula for calculating the exclusive range?
r= h-l
What is the formula for calculating the inclusive range?
r= h-l+1
The sum of the absolute value of the deviations from the mean divided by the number of scores is equal to:
mean deviation ( also called the mean absolute deviation)
The sum of the deviations from the mean will always be equal to ______________.
zero (0)
What is obtained by squaring the standard deviation
we get rid rid of the negative sign so that when we do eventually sum them, they do not add up to 0
What is obtained by taking the square of the variance?
the same units with which we originally started
Which of the following is one way to represent the standard deviation?
S or SD
Which of the following is one way to represent the variance?
s2=sigma ( x-x)2/ n-1
2.342 or 5.48
Unbiased estimates are described as:
when we subtract 1 from n
page 43
Unbiased estimates
page 43
What is the range for the following set of scores: 10,15,12,18,19,16,12?
9
What is the standard deviation for the following set of scores: 10,15,12,18,19,16,12?
3.36
What is the variance for the following set of scores: 10,15,12,18,19,16,12?
11.28
What is the range for the following set of scores: 20,24,26,22,18,16,18?
10
What is the standard deviation for the following set of scores: 20,24,26,22,18,16,18?
3.60
What is the variance for the following set of scores: 20,24,26,22,18,16,18?
12.935
Which of the following sets of data has no variability?
the one with less change between numbers
ex 4,4,4,4
What is the square of the standard deviation?
is step #4 page 41 ??
variance
What is the square root of the variance?
simply the standard deviation squared
s2=s x s
If (X-M)=235, and n = 29, what is "s"?
2.85???
Which of the following must also be known in order to compute the standard deviation?
mean
Biased estimates can be used:
only to describe the characteristics of the sample
Unbiased estimates can be used:
if you intend to use the sample as an estimate of a population parameter
When using sample estimates to estimate population parameters, you should use:
unbiased statistic
As your sample size grows larger, the n-1 adjustment for the standard deviation has a:
unbiased estimate
force the standard deviation to be larger
As your sample size grows larger, your standard deviation will be:
the less of a difference there is between the biased and the unbiased estimates of the standard deviation.
If n = 24 and s = 1.56, what is the variance?
2.43????
If you have a variance of 9, your standard deviation will be:
3
square root of 9
The variance is more difficult to interpret than the standard deviation
false
Unbiased estimates are considered to be less conservative estimates.
false?? page 43
The standard deviation is sensitive to extreme scores.
true
The exclusive range is more commonly used in research articles as compared with the inclusive range.
true
A greater standard deviation indicates less variance.
false??
A small standard deviation (relative to the mean score) indicates that the majority of individuals (or data points) tend to have scores that are very close to the mean.
. a sample with a large standard deviation (relative to the mean score) tends
A standard deviation equal to 0 indicates no variance in your data.
true??
It is possible for a set of data to have no variability.
true
If you have a standard deviation of 5, your variance will be:
25
square of 5 x5