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Variance for data with multiple-observation valuesDate: 2015-10-07; view: 390. Mode for data with multiple-observation values As we already know, the mode is the most frequently occurring value. A similar concept can be used when the data are available in multiple-observation form. Example: The following data were collected on the number of blood tests a hospital conducted for a random sample of 50 days. Find the mode.
Solution: Since 29 days were given on 18 days (the number of tests that occurs most often), the mode is 29.
Suppose that a data set contains values 1. For a population of The variance is The standard deviation is 2. For a sample of The variance is The standard deviation is The arithmetic is most conveniently set out in tabular form. Example: The score for the sample of 25 students on a 5-point quiz are shown below. Find a sample variance and standard deviation.
Solution: Remark: The denominator in the formula To calculate variance we need three columns to display the computation of the quantities The necessary computations for finding Table 1.5
Thus we have
Example: The number of television sets sold per month over a two year period is reported below. Find the variance and standard deviation for the data.
Solution: Let us apply Make a table as shown below
To find standard deviation we take the square root of variance
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