After using the Create TOPS interface, the user can move on to utilize other interfaces in the Sample Adequacy tab. Potential Samples () is one available sample interface. This interface is used to identify locations where additional samples can be added to meet HPMS sample requirements.

Steps

To identify locations of additional samples, follow these steps:

1. Fill the Volume Group, FSystem, and Urban Code filters.
2. Fill the filters in the Data Completeness section if desired.
3. Select "Find Now" to have a list of segments appear in the table.
4. Manually or randomly add samples.
   • Manually: Check a row's checkbox, enter a Sample ID, select the "Add Samples" button.
   • Random: Select the "Random Select" button, specify the number of samples to be created ("Number to Randomly Select" textbox), click the "Select Samples" button, click the "Add Samples" button.

These steps are described in further detail below.

Filters

The user can search by stratum on the Potential Samples interface through the Volume Group, Functional System, and Urban Code filters at the top of the Potential Samples interface. When accessing Potential Samples through Check Adequacy or Expansion Factors, these filters will be pre-populated to reflect the selected stratum. Check Adequacy will connect to this interface through the linked, first number on each cell. Expansion Factors will connect to this interface through the links in the expanded rows.

Additional filters can also be included through the Data Completeness section. This portion contains the "Percentage of Data Items with Values" checkbox, "AADT not within [#]% of Volume Group Upper/Lower Bounds" checkbox, and "Prioritize/Weight Data Items" link. The function of these elements is described in the User Guide equivalent to this article.

After selecting values for at least the Volume Group, FSystem, and Urban Code filters, the user can click the "Find Now" button to have a list of segments appear in the table. The resulting segments include unsampled TOPS locations and existing sample sections.

The Potential Sample Table will be populated with TOPS sections within the specified Volume Group, Functional System, and Urban Code selected. Users can add samples in two ways: manual and random selection.

Manually Add Samples

To manually add samples:

1. Check the checkbox in the first column on the desired segment.
   • Checkboxes will not be present for segments already designated as samples.
   • Segments that appear red in the table do not meet AADT criteria specified in the Data Completeness section.
   • Segments that appear orange in the table do not meet segment length restrictions set by the FHWA.
   • The "Completeness" column can be used to find the segments with the most amount of data items that exist on a segment. The number in this column specifies how many data items exist (1st number) versus (/) the total amount of data items in the selected data table (2nd number). Clicking on the completeness field will display a pop-up showing a list of data items that exist.
2. Add a new sample ID by clicking the Samples column and entering a value in the textbox.
   • If no sample ID is provided before saving, one will be generated automatically in the format JF#, where the "#" is the next number incremented from the last sample ID. For example, if the last sample ID was JF1234, the next generated sample ID would be JF1235.
3. Click the "Add Samples" button to add the new samples to the samples table and data table.

Randomly Add Samples

To randomly select samples:

1. Click the "Random Select" button to open the Random Samples interface.
2. Specify the number of samples to be created by entering a value in the "Number to Randomly Select" textbox.
3. Check the "Exclude Segments not meeting AADT criteria" and "Exclude Segments not meeting length restrictions" checkboxes if desired.
   
   • Check the "Exclude Segments not meeting AADT criteria" checkbox to prevent from randomly selecting a sample that does meet the criteria specified in the Potential Samples Data Completeness section. The checkbox will be disabled in this interface if the "AADT not within…" checkbox is not checked in the Data Completeness section.
   • Check the “Exclude Segments not meeting length restrictions” checkbox to prevent samples from being randomly selected that do not meet length restrictions set by the FHWA.
4. After all desired parameters have been set, click the "Select Samples" button to randomly select the provided number of samples.
   • These samples will be given a generated sample ID in the format JF#, where the "#" is the next number incremented from the last Sample ID.
5. Finish adding the samples to the sample table and data table by clicking the "Add Samples" button on the Potential Samples interface.

Sample Table

Below the data table, in the "Sample Table" section, the number of required samples, existing samples, samples that are needed to meet requirements, and total samples can be found. The number of selected samples and total number of samples will increase or decrease by selecting segments to sample using either method above.