Average business measures values are not accurate

The values of a business measure that calculates averages may be inaccurate, if you have defined the business measure type as Integer.

The inaccuracy of the displayed value of an Average business measure is mostly because you defined in the Business Measures editor a business measure of type Integer, and usually the average values are decimal values. The calculation of an Average business measure in WebSphere® Business Monitor is done upon the completion of each instance.

Assume you are monitoring temperature and the values are 79, 102, 45, 98, 100, 65, and 100. Therefore the value of the Average business measure "avgTemp" (upon calculating the seven completed instances) is supposed to be 84.14. Bearing in mind that the Average business measure "avgTemp" type is Integer, you may expect that the value would be rounded to 84.

However, because the average is recalculated upon the completion of each instance (a temperature value update), the average value resulted from each calculation is rounded before being displayed. Hence, the displayed value of Average business measure "avgTemp" is 82.

To elaborate this more explicitly, assume that a new temperature value is calculated (new instance completed), and its value is 67. Thus the "avgTemp" business measure is recalculated with the new value 67 included. The updated "avgTemp" value is displayed with value 80, instead of 82. This is due to the accumulation of rounding that makes the net value at the end differ from the one that would result from a single calculation of the eight values.


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