The __________ ___________
or
____________ ____________ __________
What is it? Not a graph itself, but a prelude
to an important statistical graph
The Frequency Table
or
Frequency Distribution Table
What is it? Not a graph itself, but a prelude
to an important statistical graph
What do Frequency Tables List?
A frequency distribution table for
quantitative data lists, _____________,
the following:
1. All the ______________________
2. _______________________classes
3. _____________________classes
4. _________________________
classes
5. Grand total ___________________
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What do Frequency Tables List?
A frequency distribution table for
quantitative data lists, in table format, the
following:
1. All the classes of grouped data
2. Tallies of those classes
3. Frequencies of those classes
4. Relative frequencies of those classes
5. Grand total of # of classes, frequencies
and relative frequencies
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Frequency Table to Histogram
What do frequency tables enable
statisticians to construct?
__________________________
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Frequency Table to Histogram
What do frequency tables enable
statisticians to construct?
They enable construction of
histograms
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When?
When to use a frequency table?
When__________________________
_________________________ that a
graph of a distribution
_____________________________, or
when __________________________.
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When?
When to use a frequency table?
When quantitative variables take on so
many values (in so great a range or
spread) that a graph of a distribution is
clearer if nearby values are grouped
together, or when you want to draw a
histogram.
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Frequency Distribution Table for Continuous Data
What is a class on a frequency table?
_____________________________________
What is another name for a class in a frequency
table?
_____________________________________
Determine these 2 things about Classes before
constructing any Frequency Distribution
Table:
1. ___________________________________
2. ____________________________________
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Frequency Distribution Table for Continuous Data
What is a class on a frequency table?
One line on a frequency table
What is another name for a class in a frequency
table?
Continuum
Determine these 2 things about Classes before
constructing any Frequency Distribution
Table:
1. Decide the starting point of the first class
2. Choose class widths before tallying begins
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Characteristics of the Classes in
Frequency Table
1. Data is put in _______-___________________
______________________________________
2. Each class ____________________________
3. Classes are ___________________________
4. Classes all have________________________
4. Classes vary __________________________
_____________________________________
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Characteristics of the Classes in
Frequency Table
1. Data is put in classes—A class could be 1
number or more than 1 number
2. Each class represents the same variable
3. Classes are not overlapping
4. Classes all have the same width.
5. Classes vary from 4 to 20, depending on the
spread of observations in the data set
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The Conventions of Writing Classes for
Discrete Frequency Tables
Rules or Conventions for discrete classes:
1. _________________________________
2. _________________________________
3. __________________________________
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The Conventions of Writing Classes for
Discrete Frequency Tables
Rules or Conventions for discrete classes:
1. Inequalities are not required if class width = 1
2. If class width >1, use rules for continuous
classes
3. Data may never fall into > 1 class
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The Conventions of Writing Classes for
Continuous Frequency Tables
Rules or Conventions for continuous classes:
1. _________________________________________
2. _________________________________________
3. _________________________________________
4. _________________________________________
5. _________________________________________
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The Conventions of Writing Classes for
Continuous Frequency Tables
Rules or Conventions for continuous classes:
1. The first inequality ALWAYS is a less than or equal
(≤) sign
2. The second inequality is always a less than sign (<)
3. An x is written in between the two signs
4. ‘x’ should be defined
5. Data may NEVER fall into more than one class
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Other Frequency Table Definitions
Class Width
A class width is _______________________
____________________________________
_____________________________________
What is one thing class widths must be?
Class widths must ______________________
______________________________________
Number of Classes
Count ________________________________
_____________________________________
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Other Frequency Table Definitions
Class Width
A class width is the distance from the first entry
on the second line of a frequency table MINUS
the first entry on the first line of a frequency
table
What is one thing class widths must be?
Class widths must ALWAYS be consistent for
all classes in a frequency table
Number of Classes
Count the number of lines that have been filled
on a frequency table
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