Standard deviation

# Standard deviation - distributions, the following rules...

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Standard deviation The  standard deviation  is defined as the positive square root of the variance; thus, the standard  deviation of Employee A's daily earnings is the positive square root of 36, or 6. The standard  deviation of Employee B's daily earnings is the positive square root of 31,000, or about 176.  Notation s 2  denotes the variance of a sample.  σ 2  denotes the variance of a population.  s  denotes the standard deviation of a sample.   denotes the standard deviation of a population. σ Empirical rule: The normal curve One practical significance of the standard deviation is that, with mound-shaped (bell-shaped)
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Unformatted text preview: distributions, the following rules apply: The interval from one standard deviation below the mean to one standard deviation above the mean contains approximately 68 percent of the measurements. The interval from two standard deviations below the mean to two standard deviations above the mean contains approximately 95 percent of the measurements. The interval from three standard deviations below the mean to three standard deviations above the mean contains approximately all the measurements....
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## This note was uploaded on 11/15/2011 for the course QMST 2333 taught by Professor Mendez during the Fall '08 term at Texas State.

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