Using the Single Sample T-Test Operator


The TIBCO Streaming® Single T-Test Operator is used to compute the single sample t-test.

Single Sample T-Test Properties

This section describes the properties you can set for this adapter, using the various tabs of the Properties view in StreamBase Studio.

General Tab

Name: Use this required field to specify or change the name of this instance of this component, which must be unique in the current EventFlow module. The name must contain only alphabetic characters, numbers, and underscores, and no hyphens or other special characters. The first character must be alphabetic or an underscore.

Operator: A read-only field that shows the formal name of the operator.

Class name: Shows the fully qualified class name that implements the functionality of this adapter. If you need to reference this class name elsewhere in your application, you can right-click this field and select Copy from the context menu to place the full class name in the system clipboard.

Start options: This field provides a link to the Cluster Aware tab, where you configure the conditions under which this adapter starts.

Enable Error Output Port: Select this check box to add an Error Port to this component. In the EventFlow canvas, the Error Port shows as a red output port, always the last port for the component. See Using Error Ports to learn about Error Ports.

Description: Optionally enter text to briefly describe the component's purpose and function. In the EventFlow Editor canvas, you can see the description by pressing Ctrl while the component's tooltip is displayed.

Operator Properties Tab

Property Description
Log Level Controls the level of verbosity the adapter uses to send notifications to the console. This setting can be higher than the containing application's log level. If set lower, the system log level is used. Available values, in increasing order of verbosity, are: OFF, ERROR, WARN, INFO, DEBUG, TRACE.
Missing data deletion If casewise missing data deletion is selected, then all rows with missing data in at least one of the selected variables will be excluded from the analysis, otherwise if pairwise is selected, each correlation between a pair of variables will include all cases with valid data on both of those variables.
Test mean(s) against user defined constant This constant will be used as the null hypothesized value of the mean across all variables for each single sample t-test unless otherwise specified on the Constants tab.

Constants Tab

Use this tab to specify different constants or null hypothesized values of the mean for one or more response variables. If a response variable has not been specified on this tab, then the user defined constant specified on the Operator Properties will be used.

Column Description
Field The name of the response variable
Constant The null hypothesized value of the mean to be used in the single sample t-test

Field Select tab

Property Description
Variable list Specify the list of variables for the analysis. Regular expression matching is supported.

Cluster Aware Tab

Use the settings in this tab to allow this operator or adapter to start and stop based on conditions that occur at runtime in a cluster with more than one node. During initial development of the fragment that contains this operator or adapter, and for maximum compatibility with TIBCO Streaming releases before 10.5.0, leave the Cluster start policy control in its default setting, Start with module.

Cluster awareness is an advanced topic that requires an understanding of StreamBase Runtime architecture features, including clusters, quorums, availability zones, and partitions. See Cluster Awareness Tab Settings on the Using Cluster Awareness page for instructions on configuring this tab.

Concurrency Tab

Use the Concurrency tab to specify parallel regions for this instance of this component, or multiplicity options, or both. The Concurrency tab settings are described in Concurrency Options, and dispatch styles are described in Dispatch Styles.


Concurrency settings are not suitable for every application, and using these settings requires a thorough analysis of your application. For details, see Execution Order and Concurrency, which includes important guidelines for using the concurrency options.

Operator Ports

The operator expects that the variables or fields to be analyzed are of type 'double'. The output tuple will consist of the incoming data passed through along with a list of the following analytic results for each pair of variables analyzed:

  1. Name of variable

  2. Value of constant (or null hypothesized value of mean)

  3. Mean

  4. Standard deviation

  5. N

  6. Test statistic

  7. Degrees of freedom

  8. P-value