Workspace Node: K-Nearest Neighbors - Specifications - Sampling Tab

In the K-Nearest Neighbors node dialog box, under the Specifications heading, select the Sampling tab to access options to divide the data into prototype and test samples. The testing sample is used  to create a set of new query points for which the outcomes are estimated from the known values of the K nearest cases in the prototype sample.

Element Name Description
Sampling Following are descriptions of the options in this group box.
Use random sampling Select this option button to divide the data into prototype and testing samples in a random manner. Statistica KNN uses a uniform random number generator to achieve this.
Size of training sample (%) In this field, specify the percentage of the valid cases (determined by case selection conditions) in the data set to be used to construct the prototype sample. Any remaining valid cases will be used to form the test sample.
Seed In this field, specify the random number generator seed to be used in the process of (randomly) dividing the data into prototype and test samples.
Use sample variable A sample variable is a variable in the data set that can be used to indicate case subsets. It must be a nominal variable with values taken from the set. Such variables can be generated from Statistica Spreadsheet capabilities.
Testing sample You can use a set of cases for forming your prototype sample. Click the Testing sample button to display the Test-Sample dialog box, where you can switch the Sample option on or off as well as select a variable that will be used as the sample identifier variable.
Use first N cases Select this option button to select the first N valid cases (determined by the case selection conditions) of the data set as the prototype sample. Any remaining valid cases will be used as a testing sample. You should use this option only if you have good reasons to believe that the first N cases in the data set make a good prototype sample (i.e., a sample that is a good representative of the original data set).
First N In this field, specify the number of first N cases to be used as the prototype sample.

Options / C / W. See Common Options.

OK Click the OK button to accept all the specifications made in the dialog box and to close it. The analysis results will be placed in the Reporting Documents node after running (updating) the project.