STAT EXAM1 - CHAP 2 Theory Q
What scale of measurement was used to measure the scores in the distribution shown in the following graph?
(see Q22) interval or ratio
What is the shape for the distribution show in the following graph?
(see Q26) positively skewed
A skewed distribution typically has ___ tail(s) and a normal distribution has ____ tail(s).
1, 2
What is the total number of scores for the distribution shown in the following table? X f 4 3 3 5 2 4 1 2
14
For the following distribution of quiz scores, if a score of X = 3 or higher is needed for a passing grade, how many individuals passed? X f 5 6 4 5 3 5 2 3 1 2
16
For the following distribution of quiz scores, How many individuals had a score of X = 2? X f 5 6 4 5 3 5 2 3 1 2
3
For the following frequency distribution of exam scores, how many students had scores lower than X = 80? X f 90-94 3 85-89 4 80-84 5 75-79 2 70-74 1
3
In a grouped frequency distribution one interval is listed as 50-59. Assuming that the scores are measuring a continuous variable, what are the real limits of this interval?
49.5 and 59.5
For the following distribution, what is the width of each class interval? X f 20-25 2 15-19 5 10-14 4 5-9 1
5
For the following distribution, how many people had scores greater than X = 14? X f 20-25 2 15-19 5 10-14 4 5-9 1
7
A sample of n = 15 scores ranges from a high of X = 11 to a low of X = 3. If these scores are placed in a frequency distribution table, how many X values will be listed in the first column?
9
If a set of exams scores forms a symmetrical distribution, what you conclude about the students scores?
About 50% of the students had high scores and the rest had low scores
If the following distribution was shown in a histogram, the bar above the 15-19 interval would reach from _____ to _____. X f 20-25 2 15-19 5 10-14 4 5-9 1
X=14.5 to X=19.5
In a frequency distribution graph, frequencies are presented on the ____ and the scores (categories) are listed on the ___.
Y-axis; X-axis
A researcher records the number of traffic tickets issued in each county along the New York State thruway. If the results are presented in a frequency distribution graph, what kind of graph should be used?
a bar graph
The classrooms in the Psychology department are numbered from 100 to 108. A professor records the number of classes held in each room during the fall semester. If these values are presented in a frequency distribution graph, what kind of graph would be appropriate?
a bar graph
What kind of frequency distribution graph shows the frequencies as bars that are separated by spaces?
a bar graph
What kind of frequency distribution graph shows the frequencies as bars, with no space between adjacent bars?
a histogram
The normal distribution is an example of
a smooth curve showing data from a population
For the following distribution, how many people had scores less than X = 19? X f 20-25 2 15-19 5 10-14 4 5-9 1
cannot be determined
For the following distribution, what is the highest score? X f 20-25 2 15-19 5 10-14 4 5-9 1
cannot be determined
For the following frequency distribution of exam scores, what is the lowest score on the exam? X f 90-94 3 85-89 4 80-84 5 75-79 2 70-74 1
cannot be determined
For the following frequency distribution of quiz scores, how many individuals took the quiz? X f 5 6 4 5 3 5 2 3 1 2
n = 21
The students in a psychology class seemed to think that the midterm exam was very easy. If they are correct, what is the most likely shape for the distribution of exam scores?
negatively skewed
If a frequency distribution is shown in a bar graph, what scale was used to measure the scores?
nominal or ordinal
In a distribution with a positive skew, scores with the highest frequencies are ___.
on the left side of the distribution
What frequency distribution graph is appropriate for scores measured on a nominal scale?
only a bar graph
What time is used to describe the shape of distribution in which the scores pile up on the left-hand side of the graph and taper off to the right?
positively skewed
