2.1-2.3 Review
What is the difference between a frequency polygon and an ogive?
A frequency polygon displays class frequencies while an ogive displays cumulative frequencies.
What is the difference between class limits and class boundaries?
Class limits are the least and greatest numbers that can belong to the class. Class boundaries are the numbers that separate classes without forming gaps between them. For integer data, the corresponding class limits and class boundaries differ by 0.5.
After constructing a relative frequency distribution summarizing IQ scores of college students, what should be the sum of the relative frequencies?
If percentages are used, the sum should be 100%. If proportions are used, the sum should be 1.
Why should the number of classes in a frequency distribution be between 5 and 20?
If the number of classes in a frequency distribution is not between 5 and 20, it may be difficult to detect any patterns.
What are some benefits of representing data sets using frequency distributions?
Organizing the data into a frequency distribution can make patterns within the data more evident.
What is the difference between relative frequency and cumulative frequency?
Relative frequency of a class is the percentage of the data that falls in that class, while cumulative frequency of a class is the sum of the frequencies of that class and all previous classes.
What is the definition of mode?
The data entry that occurs with the greatest frequency.
What is the definition of mean?
The sum of the data entries divided by the number of entries.
What is the definition of median?
The value that lies in the middle of the data when the data set is ordered.
what does the mean represent
the center
what does the median represent
the center
how many bars equal how many what
classes
What are some benefits of using graphs of frequency distributions?
It can be easier to identify patterns of a data set by looking at a graph of the frequency distribution.
where can you find the approximate number
at the top of the line graph
