CNSL 503 FINAL EXAM WITH VERIFIED QUESTIONS
AND ANSWERS | NEW AND UPDATED VERSION |
GRADED A+
calculate the range for the following scores: 45, 64, 32, 58, 43
Range = Xmax - Xmin
range = 64 -32
=32
Which of the following is a measure of variability?
- mean
- median
- range
- mode
range
what is central tendency?
one way to describe data; it is an average or middle value that describes
the center of a distribution. Mean, median, and mode are three measures
of central tendency
True or false: outliers are always the result of errors in data collection
FALSE! outliers may be legitimate values that should be included in the
results
True or false: frequency tables are used to display both qualitative and
quantitative data.
TRUE! displays the number of times a certain value appears within the
dataset (frequency). One of the easiest ways to summarize a set of score
or values.
identify the mode in the following set of scores: 438, 421, 423, 432, 440,
435, 441
,there is no mode because every value appears the same amount of times
(once)
Why are pie charts not used frequently be researchers and statisticians?
the effectiveness of pie charts is limited to datasets with only a few
categories
My answer: they are best with a small number of relative frequencies -
too many "slices" make it difficult to interpret the pie chart
the sum of all relative frequencies in a dataset will always equal
____________.
1 or 100%
Calculate the mean for the following set of scores: 89, 75, 91, 68, 72, 83,
94, 78
mean (x̄) = ∑ (sum of) X / n
x̄ = (89 + 75 + 91 + 68 + 72 + 83 + 94 + 78) / 8
= 81.25
true or false: the median is affected by outliers
FALSE! Neither the mode nor median is affected by outliers. It IS possible
for the mean to be affected.
a neuropsychologist records the scores on the MMSE (Mini-Mental State
Examination) for 30 patients. Every score appears once in the dataset.
What would this distribution be known as?
- multimodal distribution
- uniform distribution
- bimodal distribution
- unimodal distribution
Answer: Uniform distribution. Explanation: distribution can be described
by shape and symmetry. The number of peaks is determined by # number
of modes. Since there is no mode it is uniform distribution.
,determine the median for the following set of scores: 2121, 2115, 2117,
2120, 2118, 2122
First put in order from least to greatest (2115, 2117, 2118, 2120, 2121,
2122). Then find the middle number. If there is two take the mean of the
two.
(2118 + 2120) / 2 = 2119
the bars of __________ do not touch because they represent discrete
values, whereas the bars of ________ do touch because they represent
continuous values
Answer: bar graph; histogram Explanation: each bar in a bar graph/bar
chart represents an individual category.
Aaron scores a mean of 85 (s = 8) on 4 of his cognitive psychology exams
for fall semester. Kyle scores a mean of 83 (s = 4) on the cognitive
psychology exams. Does Aaron or Kyle have the more consistent
performance on the exams?
Kyle because his standard deviation (s) was lower, which indicates less
variability in his test scores compared to aaron
Which type of graph clearly depicts the shape of a distribution?
FREQUENCY POLYGON because the increasing and decreasing sections of
the data can be seen
In a symmetrical distribution, what is the most commonly used measure
of central tendency?
Answer: MEAN Note: in a symmetrical distribution, the
mean/median/mode are all the same value
researchers are studying the average miles per gallon (mpg) of different
cars based on size (compact, mid-size, and full-size) and make (Ford,
Chevy, and Chrysler). Would a three dimensional graph be appropriate to
use to display these data? Explain.
, Yes because there are three variables being measured (mpg, car size, and
car make). So a three dimensional graph would be the best choice.
three dimensional graph is best for "three dimensional data"
seven food trucks are competing to see how many customers visit their
trucks per day in a busy part of the city. The average number of
customers that visit each food truck per day is 281. The sum of squares is
found to be 187. calculate the variance for these data
s² or σ² (variance) = ∑ (X - x̄)^2 / (n - 1) and ∑ (X - x̄)^2 = SS (sum of
squares)
variance = sum of (term in data set - sample mean) squared / (sample
size - 1)
sum of squares = 187
s² = 187 / (7-1)
= 31.17
a gardener has 5 apple trees in her yard. Each tree has a different
number of apples growing on it. The following list represents the number
of apples on each tree: 22, 29, 31, 23, 27. Calculate the standard
deviation of these values (x̄ = 26.4)
Standard deviation (s) = √ (variance)
√ ∑ (X - x̄)^2 / (n - 1) and ∑ (X - x̄)^2 = SS. So, ∑ (19.36 + 6.76 + 21.16 +
11.56 + 0.36) = 59.2
√ (59.-1) = √ 14.8
= 3.85
a professor posts the final exam grades for 50 of his psychology students.
Most of the scores are clustered on the lower side of the distribution,
with a few scores falling toward the right. What term would be best
describe the distribution? what does this imply about how hard the test
was?
this would be considered a positively skewed (right-skewed) distribution,
as most of the scores fall on the left side of the distribution and the skew
AND ANSWERS | NEW AND UPDATED VERSION |
GRADED A+
calculate the range for the following scores: 45, 64, 32, 58, 43
Range = Xmax - Xmin
range = 64 -32
=32
Which of the following is a measure of variability?
- mean
- median
- range
- mode
range
what is central tendency?
one way to describe data; it is an average or middle value that describes
the center of a distribution. Mean, median, and mode are three measures
of central tendency
True or false: outliers are always the result of errors in data collection
FALSE! outliers may be legitimate values that should be included in the
results
True or false: frequency tables are used to display both qualitative and
quantitative data.
TRUE! displays the number of times a certain value appears within the
dataset (frequency). One of the easiest ways to summarize a set of score
or values.
identify the mode in the following set of scores: 438, 421, 423, 432, 440,
435, 441
,there is no mode because every value appears the same amount of times
(once)
Why are pie charts not used frequently be researchers and statisticians?
the effectiveness of pie charts is limited to datasets with only a few
categories
My answer: they are best with a small number of relative frequencies -
too many "slices" make it difficult to interpret the pie chart
the sum of all relative frequencies in a dataset will always equal
____________.
1 or 100%
Calculate the mean for the following set of scores: 89, 75, 91, 68, 72, 83,
94, 78
mean (x̄) = ∑ (sum of) X / n
x̄ = (89 + 75 + 91 + 68 + 72 + 83 + 94 + 78) / 8
= 81.25
true or false: the median is affected by outliers
FALSE! Neither the mode nor median is affected by outliers. It IS possible
for the mean to be affected.
a neuropsychologist records the scores on the MMSE (Mini-Mental State
Examination) for 30 patients. Every score appears once in the dataset.
What would this distribution be known as?
- multimodal distribution
- uniform distribution
- bimodal distribution
- unimodal distribution
Answer: Uniform distribution. Explanation: distribution can be described
by shape and symmetry. The number of peaks is determined by # number
of modes. Since there is no mode it is uniform distribution.
,determine the median for the following set of scores: 2121, 2115, 2117,
2120, 2118, 2122
First put in order from least to greatest (2115, 2117, 2118, 2120, 2121,
2122). Then find the middle number. If there is two take the mean of the
two.
(2118 + 2120) / 2 = 2119
the bars of __________ do not touch because they represent discrete
values, whereas the bars of ________ do touch because they represent
continuous values
Answer: bar graph; histogram Explanation: each bar in a bar graph/bar
chart represents an individual category.
Aaron scores a mean of 85 (s = 8) on 4 of his cognitive psychology exams
for fall semester. Kyle scores a mean of 83 (s = 4) on the cognitive
psychology exams. Does Aaron or Kyle have the more consistent
performance on the exams?
Kyle because his standard deviation (s) was lower, which indicates less
variability in his test scores compared to aaron
Which type of graph clearly depicts the shape of a distribution?
FREQUENCY POLYGON because the increasing and decreasing sections of
the data can be seen
In a symmetrical distribution, what is the most commonly used measure
of central tendency?
Answer: MEAN Note: in a symmetrical distribution, the
mean/median/mode are all the same value
researchers are studying the average miles per gallon (mpg) of different
cars based on size (compact, mid-size, and full-size) and make (Ford,
Chevy, and Chrysler). Would a three dimensional graph be appropriate to
use to display these data? Explain.
, Yes because there are three variables being measured (mpg, car size, and
car make). So a three dimensional graph would be the best choice.
three dimensional graph is best for "three dimensional data"
seven food trucks are competing to see how many customers visit their
trucks per day in a busy part of the city. The average number of
customers that visit each food truck per day is 281. The sum of squares is
found to be 187. calculate the variance for these data
s² or σ² (variance) = ∑ (X - x̄)^2 / (n - 1) and ∑ (X - x̄)^2 = SS (sum of
squares)
variance = sum of (term in data set - sample mean) squared / (sample
size - 1)
sum of squares = 187
s² = 187 / (7-1)
= 31.17
a gardener has 5 apple trees in her yard. Each tree has a different
number of apples growing on it. The following list represents the number
of apples on each tree: 22, 29, 31, 23, 27. Calculate the standard
deviation of these values (x̄ = 26.4)
Standard deviation (s) = √ (variance)
√ ∑ (X - x̄)^2 / (n - 1) and ∑ (X - x̄)^2 = SS. So, ∑ (19.36 + 6.76 + 21.16 +
11.56 + 0.36) = 59.2
√ (59.-1) = √ 14.8
= 3.85
a professor posts the final exam grades for 50 of his psychology students.
Most of the scores are clustered on the lower side of the distribution,
with a few scores falling toward the right. What term would be best
describe the distribution? what does this imply about how hard the test
was?
this would be considered a positively skewed (right-skewed) distribution,
as most of the scores fall on the left side of the distribution and the skew
