Midterm 1: chapter 1, 2, 3 Flashcards
1
Q
which distribution is the most homogeneous given the following: (1) mean = 100 and variance = 25; (2) mean = 120and variance = 36; (3) mean = 90 and variance = 49?
A
(1) mean = 100 and variance = 25
2
Q
the level of measurement that, at best, can rank subjects is ______?
A
nominal
3
Q
what is the appropriate procedure for weighting the score on the final examination to count twice as much as the midterm examination score?
A
Double the T score for the final and add this to the T score for the midterm.
4
Q
What happens to the mean and the standard deviation of a set of score scores if each score is increased by 10?
A
The mean changes and the standard stays the same
5
Q
Assume that a teacher wants to grade on the curve. The average grade will be a C. She will give 10% of the class an A and 10% an F. What is the T-score cutoff to pass the test (i.e., earn a grade of D or better)? Round to the nearest whole number. (Hint: Find the z score from the table of normal-curve areas.)
A
37
6
Q
Reaction-time tests are what level of measurement?
A
ratio
7
Q
On a knowledge test, a score of 10 is at the 40th percentile. What does this indicate?
A
40 percent of the test scores were at or below 10.
8
Q
What percent of the cases would you find in a distribution between the median and P15?
A
25%
9
Q
The standard deviation is an indication of ___?
A
the variability of a set of test scores around the mean
10
Q
the most stable measurement of central tendency with interval data is the_____?
A
mean
11
Q
the best reason for using T scores with three skill items on a basketball test is to ___?
A
add scores together
12
Q
three of the following four things have something in common. Which one doesn’t belong.
Mean, Range, Standard Deviation, or Variance
A
mean
13
Q
which of the following contain an absolute zero point?
A
ratio
14
Q
you want to make the norms as easy as possible for students, parents, administrators, and teachers to understand. How would you report your results?
A
raw scores and percentiles
15
Q
consider the following scores: 2,3,3,4. What is the standard deviation. Round the the nearest tenth.
A
7
16
Q
Kelly’s T score was 60. what is her Z score?
A
1.0
17
Q
which of the following tests will carry the greatest weight if you simply add the total number of correct items to obtain a total score for the course grade?
A
items = 200; mean = 120; standard deviation = 40
18
Q
who did best relative to his or her classmates? that is, who had the highest percentile?
A
unable to determine from data given
19
Q
the average number of points scored by NBA teams last year was 100 per game. the standard deviation was 30 points. Ninety-five percent of the games had NBA teams scoring fewer than how many points? Round to the closet whole number.
A
150
20
Q
what percent of observations lies between -1.96 and +1.96 standard deviations?
A
95%
21
Q
ranking scores on a test from highest to lowest facilitates finding which of the following measures?
A
median and mode
22
Q
a pupil attains a raw score of 82 on a test with a mean of 100 and a standard deviation of 12. what is the corresponding T score?
A
35
23
Q
scholastic aptitude test (SAT) scores are normally distributed with a mean of 500 and a standard deviation of 100. a student’s SAT score is 430. what is the student’s percentile? round to the nearest whole number.
A
24
24
Q
the average athlete is able to begin activity 90 days after having a knee operation. the standard deviation is 20 days. sixty-eight percent of athletes are able to participate within how many days? round to the nearest day.
A
99
25
which of the following does not belong with the other two?
a. T score = 70
b. Z score = 2.0
c. percentile = 95
26
the Z score at the 70th percentile is ?
0.52
27
which pair of scores represents the same level of measurement?
distance and height
28
what is the simplest measure of variability to calculate?
range
29
what is the mean of a T score?
50
30
what percentage of the normal curve lies between -1.53 and +1.37 standard deviation units from the mean?
85.17
31
what is the T score associated with the 97.5th percentile?
70
32
which of the following does not represent a nominal scale of measurement?
height
33
How can a standard z score be changed to a T score?
multiply by 10 and add 50
34
Which of the following measurement scales is related to naming or classifying?
nominal
35
Distribution that has many more high scores than low scores is____?
negatively skewed
36
Distribution around a given mean and standard deviation that is mesokurtic with no skewness is said to be
normal
37
how many students out of 100 would be between the z score of .33 and .94?
20
38
put score limits on 95 percent of the scores when the 84th percentile is a score of 60 and the 16th percentile is a score of 50
45 to 50
39
with a mean of 27.1 and a standard deviation if 3.9, the T scores for the raw scores 26 and 32 are
47 and 63
40
mean = 196, standard deviation = 14, and N=17. What is the raw score for a z score of 0.35?
201
41
John scored at the 45th percentile on the course midterm. Which interpretation go his score is the best?
John had a better score than 45% of the people tested.
42
which of the following is not affected by the value of every score in the set on which it is calculated?
median
43
for a set of 5,000 scores, the mean is 98, the median is 110, and the mode is 120, which describes the distribution?
negatively skewed
44
for a 100 point test, the cutoff for an F is 60 points. With a mean of 74 and standard deviation of 10, how many students out of 100 would receive an F?
8
45
SAT scores are normally distributed with a mean of 500 and a standard deviation of 100. A students SAT score was at the 30th percentile. what was her raw score? round to the nearest whole number.
448
46
what score represents P16 if the mean of the distribution is 300 and the standard deviation is 10?
290
47
in a normal distribution, the mean divided by the median equals _____?
1
48
why are standard scores so important?
they permit scores to be compared more appropriately
49
you are discussing the heterogeneity of your tennis class results with one of your fellow teachers. which of the following terms will you probably use in the discussion?
standard deviation
50
the mean on a test was 50 and the standard deviation was 20. what percent of people scored between a Z score of .80 and raw score of 68?
2.78
51
the mean on a test was 200 and the standard deviation was 20 points. what percent of people scored less than 170? round to the nearest whole number.
7
52
given that the mean is 80 and the standard deviation is 10, which of the following does not belong?
P = 38.69
53
what area of the normal curve lies between a Z score of .48 and a T score 0f 42?
0.00
54
given the variance = 100 and P16 = 985, which of the following is probably the mean?
995
55
T score = 43. what is the percentile?
24.20
56
which of the following represents the nominal scale of measurement?
student number
57
which of the following measure represents the highest degree of relative performance?
T score 72
58
what is the T score for the 43rd percentile?
48.20
59
what is the mean of a Z score distribution?
0
60
what T score value is associated with a score of 15 from a distribution having a mean and standard deviation of 25 and 10, respectively?
40
61
to make statements such as 8 units is twice as much as 4 units, what level of measurement is required?
ratio
62
the numbers on the shirts of football referees represent what level of measurement?
nominal
63
approximately what percentile is associated with a raw score located 1 standard deviation below the mean in a normal distribution?
16
64
what score from a distribution having a mean of 30 and a standard deviation of 5 corresponds to a z score of -1.5?
22.50
65
what percentage of the normal curve lines between -2.0 and +2.0 standard deviation units from the mean?
95.44
66
if a normal distribution of scores has a mean of 47 and a standard deviation of 11, what range of the values would contain 99.74% of the scores?
14 to 80
67
if IQ scores are normally distributed with a mean of 100 and a standard deviation of 15, what percentage of the population has IQs between 85 and 130?
81.85
68
lining students up according to height without actually measuring height represents what level of measurement?
ordinal
69
given the following statistics, which test would contribute most to a composite score obtained by adding each student's four scores together?
test D: M = 50; SD = 8
70
(True/False) the larger the standard deviation, the more homogeneous the distribution.
false
71
(true/false) the first quartile corresponds to the 75th percentile value.
false
72
a distribution of scores is best obtained with what PASW command?
frequencies
73
(True/False) measurement on the nominal scale is accurately described as quantitative measurement.
false
74
(true/false) the area to the left of 1 standard deviation from the mean in a normal distribution represents 84% of the total area of the curve.
true
75
which of the following represents the nominal scale of measurement?
student enrollment (ID) number
76
who did best relative to his or her classmates? that is, who had the highest percentile?
it is impossible to determine from what is given
77
Karen's T score was 65. What is her Z score?
1.5
78
the mean on a test is 200 and the variance was 400 points. what percentage of people scored less than 170? round to the nearest whole number.
7
79
political party affiliation (republican, democrat) is an example of which measurement scale?
nominal scale
80
classifying subjects as athletes or non athletes, male or female, from new york or hawaii, is an example of which measurement scale?
nominal scale
81
oxygen uptake capacity measured in liters per minute is an example of which type of measurement?
ratio scale measurement
82
which of the following statistics are most commonly reported in sport and exercise science research reports?
mean: standard deviation
83
which of the following is a characteristic of ratio scale measures?
they have absolute zero values
84
which of the following is a characteristic of ordinal scale measures?
they indicate rank order
85
which measure of variability is normally reported with the mean?
standard deviation
86
which measure of central tendency is most appropriate for ordinal scale measurements?
median
87
which of the following is the highest (most sophisticated) sale of measurement?
ratio
88
what is summation notation?
a shorthand method of describing mathematical steps
89
which measure of central tendency is most appropriate for continuous scale measurements?
mean
90
when are the mean, median, and mode identical?
when the distribution is symmetrical
91
which words might be used to describe the shape of a distribution?
skewness
92
why is the range not often used for statistical analysis?
it is not very reliable
93
what is another name for the Z score table?
normal curve table
94
which of the following is not a PASW command that you can use to summarize your data?
cluster
95
what percentage of the cases would you find in a distribution between the median and Q3?
25%
96
(True/False) forced categories should not be created because of the potential loss of information.
true
97
(True/false) the total area to the left of -1 standard deviation from the mean in a normal distribution represents approximately 84% of the total area of the curve.
false
98
how does one describe a distribution that has many more high scores than low scores?
negatively skewed
99
with a mean of 12 and a median of 14, we can infer that the distribution is ?
negatively skewed
100
with a median of 12 and a mean of 14, we can infer that the distribution is?
postively skewed
101
the Z score of 1.56 is what percentile?
94.06
102
the Z score of -.50 represents what percentile?
30.85
103
the graphing technique that inmost appropriate for depicting the shape of a single set of data is a?
histogram
104
to compare two sets of data, the most appropriate technique to use is the?
frequency polygon
105
a distribution that has a large number of scores that cluster close to the mean with relatively few scores falling in either tail is said to be?
leptokurtic
106
the best estimate of the median of the measurements5, 7, 8, 10, 11, 12, 13, and 18 is?
10.5
107
in a fairly large, normal distribution with a mean of 15.0, two-thirds of the cases fall between the score points 12.5 and 17.5. the standard deviation can be estimated to be close to
2.5
108
(true/false) the sum of the deviation scores from the mean will always be zero.
true
109
descriptive statistics provide?
mathematical summaries of data
110
the variables height (in inches), gender, and race would be considered ____, _____, and ______, respectively.
continuous; nominal; nominal
111
the variables age (in years), sport, and college major would be considered ____, _____, and ____, respectively.
continuous; nominal; nominal
112
the variables percent body fate (%), oxygen consumption (ml/kg/min), and eight ( in pounds) would be considered ____, ____, and _____, respectively.
continuous; continuous; continuous
113
the variable BMI group (low, normal, high, very high) would be considered?
ordinal
114
the variable weight (in kg) would be considered?
continuous
115
the variables time ( in seconds), temperature (in degrees F), and triathlon event (swim, bike, run) would be considered ___, ____, and ____, respectively.
continuous; continuous; nominal
116
which if the following is the arithmetic average?
| mean, median, mode, variance
mean
117
when you sum all of the X values of interest and divide by the number of values that you summed, you have calculated a?
mean
118
which statistic can be used with either continuous, nominal, or ordinal data?
mode
119
which statistic requires the data to be ranked before its calculation?
median
120
if a distribution of test scores has an usually high score in comparison to the other scores, what shape does it have?
skewed right
121
which of the following allows for fractional comparison?
| nominal, ordinal, interval, ratio
ratio
122
which of the following graphs is the best choice in determining the shape of a distribution?
bar chart, histogram, pie chart, frequency table
histogram
123
total score variance minus error score variance leaves you with?
true score variance
124
if everyone in a classroom scores the same on an exam, the variance is?
0
125
if a normal distribution of scores has a mean of 70 and a standard deviation of 10, what score does it take to be 2 standard deviations above the mean?
90
126
if a normal distribution of scores has a mean of 70 and a standard deviation of 10, approximately what percentage of students scored below 60?
16.0
127
assume that resting heart rates are normally distributed with a mean of 80 beats per minute and a standard deviation of 8 beats per minute. what is the Z score of a heart rate of 95 beats per minute?
1.88
128
assume that resting heart rates are normally distributed with a mean of 80 beats per minute and a standard deviation of 8 beats per minute. what is the probability of randomly selecting a person with a heart rate of 95 beats per minute or greater?
0.030
129
the statistical term for the shape (or symmetry) of a distribution is _____ and the peakedness of a curve is referred to as ______.
kurtosis; skewness
130
what are the two commonly used standard scores?
Z score and T score
131
Class A had a mean test score of 85 with a standard deviation of 15 while class B had a mean test score of 80 with a standard deviation of 10. what can be implied?
class A performed better than class B but were less homogenous.
132
if a distribution of cholesterol scores has a mean of 260, median of 200, and mode of 200, it is likely that the distribution is?
positively skewed
133
if a distribution of cholesterol scores has a mean 200, median of 170, and mode of 160, it is likely that the distribution is?
positively skewed
134
if a distribution of cholesterol scores has a mean of 150, median of 200, and mode of 200, it is likely that the distribution is?
negatively skewed
135
when using the table of normal-curve areas, it is important to remember that?
- the reference point is the mean
- Z scores are presented to the nearest hundredth
- Z scores are at the left and top margins
- percentages are located in the body of the table
136
(True/False) the mean, median, and mode all measure the spread of a distribution.
false
137
(true/false) if a data set includes values that are all close in range with the exception of one value, which is much larger than all the others, the mean is the best measure to describe the distribution.
false
138
(true/false) a student collects the jersey numbers from athletes on a college sports team. the mean would be an appropriate measure to describe the distribution.
false
139
(true/false) a sample variance describes the average distance that each sample observation is from their mean.
false
