Databases Reference
In-Depth Information
Function IsOdd(ByVal lngNumber As Long) As Boolean
IsOdd = (lngNumber \ 2 <> lngNumber / 2)
End Function
Often, it is worthwhile to do an analysis of the effect outliers have on a series of data. Outliers
are data points that are located in excess of
3 Standard Deviations from the mean. If outliers
make up only a small number of data points within the data set, eliminating them from consideration
can yield quite different results. Outlier analysis can often provide insight on what is causing the
quality control problems in a process.
If the user chooses to conduct an outlier analysis, the
EliminOutliers
subroutine is
invoked, and the Averages and Standard Deviations are recalculated omitting any points that were
greater than
±
3 Standard Deviations from the originally calculated mean and standard deviation.
This is accomplished by using the
IncludePoint
function, which makes a determination if a
particular point should be included in an analysis or omitted from the analysis. Notice the callout
in Figure 10.10 that shows an instance of where only 19 of 20 points were utilized in the revised
calculation (the omission of 1 outlier).
±
Sub EliminOutliers()
'Here we extract the original data and compute the mean and
stdev using all of the data
FIGURE 10.10
Parameter report for lot with outliers omitted from calculations.
