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print qr code vb.net Normal Values in Visual Basic .NET
Normal Values Paint Code 39 In Visual Basic .NET Using Barcode creator for VS .NET Control to generate, create Code39 image in VS .NET applications. www.OnBarcode.comScan Code 3 Of 9 In VB.NET Using Barcode scanner for .NET framework Control to read, scan read, scan image in VS .NET applications. www.OnBarcode.comA normal value is the single value that occurs most often in a data set. Data Set A has a normal value of 4, Data Set B has a normal value of 3, and Data Set C has a normal value of 1. Generate Barcode In VB.NET Using Barcode maker for Visual Studio .NET Control to generate, create bar code image in .NET framework applications. www.OnBarcode.comBar Code Scanner In VB.NET Using Barcode decoder for VS .NET Control to read, scan read, scan image in Visual Studio .NET applications. www.OnBarcode.comStandard Deviations
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Mathematically calculating statistical significance, or reliability, based on sample size is a task that is too arduous and complex for most commercially driven softwaredevelopment projects. Fortunately, there is a commonsense approach that is both efficient and accurate enough to identify the most significant concerns related to statistical significance. Unless you have a good reason to use a mathematically rigorous calculation for statistical significance, a commonsense approximation is generally sufficient. In support of the commonsense approach described below, consider this excerpt from a StatSoft, Inc. (http://www.statsoftinc.com) discussion on the topic: There is no way to avoid arbitrariness in the final decision as to what level of significance will be treated as really significant. That is, the selection of some level of significance, up to which the results will be rejected as invalid, is arbitrary. Typically, it is fairly easy to add iterations to performance tests to increase the total number of measurements collected; the best way to ensure statistical significance is simply to collect additional data if there is any doubt about whether or not the collected data represents reality. Whenever possible, ensure that you obtain a sample size of at least 100 measurements from at least two independent tests. Although there is no strict rule about how to decide which results are statistically similar without complex equations that call for huge volumes of data that commercially driven software projects rarely have the time or resources to collect, the following is a reasonable approach to apply if there is doubt about the significance or reliability of data after evaluating two test executions where the data was expected to be similar. Compare results from at least five test executions and apply the rules of thumb below to determine whether or not test results are similar enough to be considered reliable: 1. If more than 20 percent (or one out of five) of the testexecution results appear not to be similar to the others, something is generally wrong with the test environment, the application, or the test itself. 2. If a 90th percentile value for any test execution is greater than the maximum or less than the minimum value for any of the other test executions, that data set is probably not statistically similar. 3. If measurements from a test are noticeably higher or lower, when charted sidebyside, than the results of the other test executions, it is probably not statistically similar. Figure 15.7 Result Comparison 4. If one data set for a particular item (e.g., the response time for a single page) in a test is noticeably higher or lower, but the results for the data sets of the remaining items appear similar, the test itself is probably statistically similar (even though it is probably worth the time to investigate the reasons for the difference of the one dissimilar data set.

