Attribute Gage Study (Analytic Method) - Attribute Gage Study Tab
Select Attribute gage study (Analytic method) from the Process Analysis Procedures Startup Panel and click the OK button to display the Attribute gage study (Analytic method) dialog box, which contains one tab: Attribute gage study.
Variables
Click the Variables button to display a four-list variable selection dialog box. The variables lists include:
Part number
Contains the part name, identifier, or number that will be used for associating cases in the References, Acceptance, and Number of trials variables to the readings of the appropriate gage (part).
References
Records the reference values. These are the known and correct continuous measurements that are associated with each part.
Acceptance
Records the number of acceptances. The smallest part must have zero (0) acceptances, and the largest part must have the maximum number of acceptances (such as an acceptance for each trial, so that if Number of trials = 20, then the largest part must have 20 acceptances). See the Introductory Overview for more details.
Number of trials
This optional variable records the number of trials for each part. The number of trials for each part must be greater than or equal to 15. If you use the AIAG method (default) to test the bias of the gage, you must have exactly 20 trials per part.
Test bias = 0 using
Use the options under Test bias = 0 using to specify whether to use the AIAG method or the Regression method in testing the bias of the gage. For more information on the computations involved with each of these methods, see the Computational Details.
Binary attributes in
Use the options under Binary attributes in to specify whether raw data or aggregated counts are used.
Aggregated counts
When aggregated counts are used, you can enter the number of trials used for each part either as an optional variable (see Variables) or by entering a value in the Number of trials field. Use the Number of trials field only if the number of trials was constant for all parts. For aggregated counts, you can also enter an Attribute label. By default, Statistica assumes the values in the Acceptance variable are the number of trials in which the part was accepted, thus the Attribute label default is Acceptance.
Raw data
When raw data are used, you must select the Attribute for calculation. Double-click in the Attribute for calculation field to display the Variable Code dialog box, which lists all the codes found in the Acceptance variable so that you can select the attribute code to use in calculations (such as Accepted or Rejected).
Tolerance limit for calculation
Use the options under Tolerance limit for calculation to specify either the lower or upper tolerance limit to use in calculations.
Lower limit
Select this options button and enter a constant, lower tolerance limit to use in calculations. You should specify a lower tolerance limit when the probability of acceptance follows an increasing trend as the references increases, such as parts with a lower reference number have a lower probability of acceptance and parts with a higher reference number have a higher probability of acceptance.
Upper limit
Select this options button and enter a constant, higher tolerance limit to use in calculations. You should specify an upper tolerance limit when the probability of acceptance follows a decreasing trend as the references increases, such as parts with a lower reference number have a higher probability of acceptance and parts with a higher reference number have a lower probability of acceptance.
Display the other limit (optional)
Select this check box and enter another limit to display on the Gage Performance Curve if you want to display both an upper and lower tolerance limit. If a Lower limit is specified, the value given here should be greater than the specified Lower limit. If an Upper limit is specified, the value given here should be smaller than the specified Upper limit.
OK
Click the OK button to run the Attribute gage study analysis and display the Attribute Gage Study Results dialog box.
Cancel
Click the Cancel button to close the Attribute gage study (Analytic method) dialog box and return to the Process Analysis Procedures Startup Panel.
Case selection
Click the Case selection button to display the Analysis/Graph Case Selection Conditions dialog box, which is used to create conditions for which cases will be included (or excluded) in the current analysis. More information is available in the case selection conditions overview and syntax summary.