Measures of Central Tendency and MAD Notebook.notebook
March 29, 2016
Mean, Median, Mode, and Range Notes
Fill in the definitions for the following words
Warm-up:
Measures of Central Tendency ­ the statistical measure that identifies a single value as representative of an entire data set.
1.) candy bar, pig, baseball
Statistic
Definition
Math Calculations
Mean
The average of a data set
Sum of the data values .
The total number of data values
2.) brothers, ice, sugar
The middle value of a data set Order the numbers from least when the numbers are in to greatest and pick the middle numerical order
value
Median
Mode
The data value that occurs the most often
Mode = most often
Range
Tells the span of your data values
Maximum – Minimum Example: Use the below chart that lists the weights of students to a class to answer the following questions.
Mean, Median, Mode, and Range Notes Part 2
Choosing Measures of Central Tendency
Ex 1: Test Scores on a Science Test: 75, 87, 90, 95, 79, 95, 92, 88, 84, 42, 93, 80
What measure of central tendency would best represent this data?
Suppose Amanda enrolls in the class and her weight is 51 kg. Without computing, answer the questions.
4) How will Amanda affect the new mean?
1.) Calculate the Mean, Median, and Mode
5) How will Amanda affect the new median?
Suppose Bobby now joins the class. His weight is 70 kg.
6) When both Amanda and Bobby join the class, what are new mode, mean, and median?
Variability and Mean Absolute Deviation (MAD) Notes
Measures of Central Tendency: mean, median and mode. (one number that summaries all the points)
Measure of Variability: the number that describes how the points in a data set vary.
2.) Select the measure or measures that best describes the data values.
Example 1: Find the Mean Absolute Deviation for the dot plot shown below.
Step 1: Find the mean of the data set.
Mean: __________
Step 2: Find each data point’s distance from the mean.
Measure of Variability: Range and Absolute Mean Deviation.
Mean Absolute Deviation (MAD): the average distance between the mean and each value in the data set.
Step 3: Calculate the mean of the distances from the mean (results from step 2).
MAD: _________
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Measures of Central Tendency and MAD Notebook.notebook
Example 2: Find the Mean Absolute Deviation for the following basketball Scores: 32, 40, 41, 42, 30
Step 1: Find the mean of the data set.
March 29, 2016
Example 3: Find the Mean Absolute Deviation for the following line plot.
Step 1: Find the mean of the data set.
Mean: __________
Mean: __________
Step 2: Find each data point’s distance from the mean.
Step 2: Find each data point’s distance from the mean.
Step 3: Calculate the mean of the distances from the mean (results from step 2).
Step 3: Calculate the mean of the distances from the mean (results from step 2).
MAD: _________
MAD: _________
Comparing two sets of data using the Mean and the Mean Absolute Deviation
Example 2: Two chess clubs chose 10­person teams to compete in a chess tournament. The table shows the ages of the people on the two teams.
A) Calculate the mean and the mean absolute deviation for each team.
Team A:
Mean=______
Team B:
Mean=______
MAD=______
MAD=______
B) Write a sentence that compares the means of the two teams.
C) Write a sentence that compares the mean absolute deviations of the two teams.
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