Mean, median, mode & range

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Measures of central tendency

• All four are called measures of central tendency.
• They are short hand ways to describe a series
  of numbers
• Family income
• Grades
• Height
• Each one has strengths and weaknesses BUT none
  is a complete description of the series.

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Mean

• The mean, sometimes called the arithmetic mean,
  is the average of series of values.
• Consider the following values
• 13, 18, 13, 14, 13, 16, 14, 21, 13
• To calculate the mean, add and then divide by the
  number of values
• (13 18 13 14 13 16 14 21 13) 9
  15
• Note that the mean, in this case, isn't a value
  from the original list. This is a common result.
  You should not assume that your mean will be one
  of your original numbers.

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median

• The median is the middle value when the numbers
  are in numerical order from low to high
• 13, 13, 13, 13, 14, 14, 16, 18, 21
• There are nine numbers in the list, so the middle
  one will be the (9 1) 2 10 2 5th
  number
• 13, 13, 13, 13, 14, 14, 16, 18, 21
• The median is 14.
• The formula for the place to find the median is
  "(the number of data points  1) 2", but you
  don't have to use this formula. You can just
  count in from both ends of the list until you
  meet in the middle, if you prefer, especially if
  your list is short. Either way will work.

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median

• If the series contains an even number of values,
  the median is the average of the two middle
  values
• 13, 13, 13, 13, 14, 14, 16, 18, 21 21
• There are ten numbers in the list, so the middle
  one will be average of the two values in the
  middle.
• In this example, the median is still 14.

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mode

• The mode is the number that is repeated more
  often than any other
• 13, 13, 13, 13, 14, 14, 16, 18, 21
• 13 is the mode.
• The "mode" is the value that occurs most often.
  If no number in the list is repeated, then there
  is no mode for the list.

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Range

• The difference between the largest and smallest
  in a set of numbers.
• 13, 18, 13, 14, 13, 16, 14, 21, 13
• The largest value in the list is 21, and the
  smallest is 13,
• Range is 21 13 8.

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Description by central tendency

• Described in terms of central tendency our series
  13, 18, 13, 14, 13, 16, 14, 21, 13
• mean 15
• median 14
• mode 13
• range 8

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Federal foundation grant performance measures

• The Rapides Foundation (Central Louisiana)
• Uses change in median household income to gauge
  grantees program impact over time
• Community Development Block Grant
• We are pleased with the Citys housing
  assistance performance, in particular its
  Residential Rehabilitation program that resulted
  in repairs to thirteen (13) homes to benefit
  low-income households.
• Letter from CDBG to City of Miramar FL

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channel

• https//www.youtube.com/user/rudirae1
• If you have suggestions for new videos, drop me a
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