Measures of Central Tendency, Dispersion, IQR and standard deviation

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Measures of Central Tendency, Dispersion, IQR and
standard deviation
Unit 4
Day 93 Wednesday, March 10, 2021

• How do we describe data using statistical
  measures?

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Example 1

• Directions Find the Mean, Median, Mode, Range,
  IQR and Standard Deviation for the following data
  set.
• 4, 2, 10, 6, 10, 7, 10
• mean 7
• median 7
• mode 10
• Range 8
• IQR 6
• SD 2.98

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Example 2

• Directions Find the Mean, Median, Mode, Range,
  IQR and Standard Deviation for the following data
  set.

• mean 52.42
• median 53
• mode No Mode
• Range 39
• IQR 24
• SD 12.62

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Ex 3 If the average monthly temperature
increased by 2 degrees each month, how would this
affect the mean and standard deviation?

• The mean would increase by 2 and the standard
  deviation would remain the same.

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Ex 4 If the average monthly temperature
increased by 3 degrees in the Month of March and
July, how would this change the mean?
The mean and the standard deviation would
increase.
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Example 5

• Directions
• Find the mean number of shutouts.
• Find the interquartile range.

mean 72.8 IQR 19
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Example 6

• Directions The following is a list of lengths
  (in minutes) of 13 Movies. Find the Mean and
  Standard Deviation for the following data set.
• 90, 102, 120, 180, 90, 85, 90, 137, 120, 151, 97,
  93, 120

mean 113.46
SD 27.46
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Ex 7 The following is a list of lengths (in
minutes) of 13 Movies.

• 90, 102, 120, 180, 90, 85, 90, 137, 120, 151, 97,
  93, 120
• If all movie times increased by 10 minutes, how
  would the mean and standard deviation be
  affected?
• The mean would increase by 10 and the standard
  deviation would remain the same.
• If all movie times decreased by 5 minutes, how
  would the mean and standard deviation be
  affected?
• The mean would decrease by 5 and the standard
  deviation would remain the same.

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• Assignment Unit 4 Day 93 Handout