In: Statistics and Probability
Suppose you calculated the mean, median, mode, and sample standard deviation of a data set. The results are shown below.
Mean: 44
Median: 31
Mode: 46
Sample Standard Deviation: 2
If each number in the data set was decreased by 4 units, what would
be the new values of these statistics?
Fill in your results below.
New Mean:
New Median:
New Mode:
New Sample Standard Deviation:
Given:
Mean = 44 , Median = 31, Mode = 46, Sample standard deviation = 2
Mean = sum of all observation / Total number of observation.
If every observation is decrease by 4 , mean will be decrease by 4
New mean is 44-4 = 40
New mean is 40
Median: If we arrange data in ascending or descending order, middle value of the data is median.
If all values decrease by 4 , median value will be decrease by 4.
New median = 27
Mode = Value that having maximum frequency.
Mode will be decrease by 4.
New mode: 42
Sample standard deviation =
Even if each value is decrease by 4, deviation from each value will remains same.
There is no effect on sample standard deviation.
New sample standard deviation = 2
Please refer this sample data. We get mean . median, mode and standard deviation.
Subtract 4 by each value, we will get new sample data. Find mean . median, mode and standard deviation and compare with original data.
You can observe mean . median, mode decreased by 4, while standard deviation will remains same.