Work with populations and samples

The populations and samples feature allows you to create a subset, called a sample, of a group of documents, called a population. You can use the sample to obtain information about the population, such as assessing a new case or monitoring the quality of coding. You can also use samples with predictive coding to identify documents that are likely to be responsive, therefore expediting the document review.

You create populations and samples using binders. A population is a snapshot of the binder that is frozen at the time you create the sample. Although the documents in a binder can later change, the documents in the population remain the same. A sample consists of documents that the application randomly selects from the population. The sample is representative of the population. For instance, if you observe that 25% of the sample is coded as Privileged, then you can estimate that 25% of the population is coded as Privileged.

The information in this topic describes how to access, create, view, and modify populations and samples. It also introduces the predictive coding process.

Set security for populations and samples

Administrators and group leaders with permissions can access the Populations and Samples page. For information about how to grant administrative access to group leaders, see Grant administrative access.

To allow users to access populations and samples, you set security for populations. All samples inherit security from their population.

For information about how to set security for multiple populations at the same time, see Work with security for objects.

To set security for populations:

On the Case Home page, under Analysis, click Populations.

Click the name of a population.

In the navigation pane, click Security.

Depending on which groups you want to set security for, do the following:

To change the security for a user group, hover over the row for the group, and then select an option.

To change the security for all user groups, select an option in the heading row. Then click OK.

The following security settings are available.

Permission	Description
Deny	Denies the group access to the population and its samples.
Allow	Allows the group access to the population and its samples.

View the list of populations and samples

The Populations and Samples page uses a tree format to list all populations and samples in a case.

To view the populations and samples in a case:

On the Case Home page, under Analysis, click Populations.

Click the plus sign next to a population to view the samples within the population.

Change the size of a sample

You can increase or decrease the size of an existing sample. The application preserves the random nature of the sample to avoid sampling bias. Any document from a population appears in only one sample.

To change the sample size:

On the Case Home page, under Analysis, click Samples.

Click the plus sign next to a population to view the samples within the population, and then click the sample that you want to edit.

On the Properties page, in the Documents box, type the number of documents to include in the sample.

Click Save.

An error message appears if you exceed the maximum number of unique documents that are available for sampling in the population.

View population and sample properties

To view the properties of a population or sample:

On the Case Home page, under Analysis, click Populations.

To view the properties of a population, click the name of a population. To view the properties of a sample, click the plus sign next to the population name and then select the sample.

The following table describes the information on the Properties page.

Column	Description
Population name or Sample name	The name of the population or sample.
Description	The user-supplied description of the population or sample.
Documents	The number of documents in the population or sample.
Created date	The date and time that the population or sample was created.
Created by	The name of the user who created the population or sample.
Population (for Samples only)	The name of the population from which the sample was taken.

To view the documents in a population as a search result set, click the number under Documents. To view the documents in a sample, click the View documents button.

View a population or sample on the Documents page

Use one of the following procedures to view populations and samples on the Documents page.

On the Populations and Samples page, click the number in the Documents column.

On the Properties page of a population, click the number under Documents.

On the Properties page of a sample, click the View documents button next to the Documents box.

Delete a population or sample

You can delete a population or sample.

Note: You cannot delete a sample, or a population that contains a sample, if the sample is in use by an active prediction.

To delete a population or sample:

On the Case Home page, under Analysis, click Populations.

Do one of the following:

Select the check box next to the populations that you want to delete. If you delete a population, all samples in the population are also deleted.

Select the check box next to the samples that you want to delete.

Select the check box in the title row to select all populations and samples.

Click Delete.

Note: If a population or sample is in use by an active prediction, the population or sample and the predictive model names are listed in the confirmation message that appears. You can click the name of a predictive model to view more information or make changes.

Click OK.

Perform predictive coding using continuous active learning

Population-based predictive coding facilitates document review by using a human-reviewed sample set to make predictions about the entire population. For information about performing predictive coding using CAL, see Performing predictive coding using CAL.