> ## Documentation Index
> Fetch the complete documentation index at: https://developers.respondent.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Targeting audiences effectively
> Configure filters and signals to reach the right participants
## Determining how many participants to target
`targetNumberOfParticipants` is used to select how many participants a research intends to conduct research with. Respondent will always attempt to deliver 3X `targetNumberOfParticipants`with qualified participants but will not prevent more participant from applying to a project. We also do not restrict more participants being invited or paid in projects in case a researcher's needs grow during the course of research.
## Audience features by targetMarketType
When creating projects you will be able to use the following audience features. As noted in the table different audience features are used between B2C and B2B projects.
| Feature | B2C | B2B | Required |
| --------------------------------------------------------- | --- | --- | ---------------- |
| targetCountries | ✅ | ✅ | |
| targetCities (used with countries only) | ✅ | ✅ | |
| targetLocationRespondentInPerson (in person project only) | ✅ | ✅ | |
| targetGenders | ✅ | ✅ | |
| targetAgeGroups | ✅ | ✅ | |
| targetEthnicities | ✅ | ✅ | |
| targetEducation | ✅ | ✅ | |
| targetHouseholdIncome | ✅ | ✅ | |
| filterPastParticipation | ✅ | ✅ | |
| targetProjectTopics | ✅ | | Required for B2C |
| targetProfessionalIndustries | | ✅ | Required for B2B |
| targetCompanySize | | ✅ | |
| seniority | | ✅ | |
| targetJobFunctions | | ✅ | |
| targetJobTitles | | ✅ | |
| targetAudienceSkills | | ✅ | |
## Audience feature by type (filters vs signals)
Audience features have 2 different implementations to ensure projects can be filled appropriately. Some features are used as filters while others are used as signals.
**Filters**
Filter type audience features restrict which participant have access to apply to projects. If a filter type audience feature is applied to a project participants will only be able to apply to the project if their profile matches the selected feature.
**Signals**
Signal type audience features influence Respondent's matching algorithm and determine which participants are contacted to fill the project via a fuzzy match, but does not restrict participants from applying if their profile is not an exact match. This will also allow more participants to organically apply to a project through their participant dashboards if they are an exact match for the filter type audience features used in a project.
You can choose to make targetHouseholdIncome, targetProjectTopics,
targetProfessionalIndustries, targetCompanySize, and targetAudienceSkills act
as hard filters for a project by turning them into [key
qualifiers](/docs/Guides/b2b-participant-qualification-and-filters).
| Feature | Filter | Signal |
| --------------------------------------------------------- | ------ | ------ |
| targetCountries | ✅ | |
| targetCities (used with countries only) | ✅ | |
| targetLocationRespondentInPerson (in person project only) | ✅ | |
| targetGenders | ✅ | |
| targetAgeGroups | ✅ | |
| targetEthnicities | ✅ | |
| filterPastParticipation | ✅ | |
| targetEducation | ✅ | |
| targetHouseholdIncome | | ✅ |
| targetProjectTopics | | ✅ |
| targetProfessionalIndustries | | ✅ |
| targetCompanySize | | ✅ |
| seniority | ✅ | |
| targetJobFunctions | ✅ | |
| targetJobTitles | | ✅ |
| targetAudienceSkills | | ✅ |
## Filter past participants
The `filterPastParticipation` field allows you to control whether participants who have previously participated in your research can apply to new projects. This is a filter-type audience feature that restricts participant access based on their participation history.
### How it works
When `filterPastParticipation` is set, the system checks if a participant has previously been paid for research conducted by the same organisation or based on the `externalResearcher` object for API.
### Using filterPastParticipation via API
Include the `filterPastParticipation` field in your [project creation request](/projects/create-a-project):
```json theme={null}
{
"publicTitle": "New Product Feedback Study",
"targetMarketType": "b2c",
"filterPastParticipation": {
"hasNeverParticipated": true,
"months": "3"}
"externalResearcher": {
"researcherId": "researcher_123",
"teamId": "team_456",
"companyId": "company_789"
},
// ... other project fields
}
```
### Using filterPastParticipation on the DIY platform
When creating a project through the Respondent platform:
1. Navigate to the project creation flow
2. In the **Audience Targeting** section, locate the **Past Participation** filter
3. Select your preference:
* **Has never participated in a project** - Only new participants can apply
* **Has never participated in a project in the last X months** - Only new participants can apply within X months
* **N/A** - No restriction
Past participation is tracked at the payment level. A participant is only
considered a "past participant" if they were marked as attended and paid for a
previous project associated with the organisation.
### Working with your participant database
If your organisation has the participant database feature enabled, you can also:
* Search past participants using the [Search past participants](/team-respondents/search-past-participants) endpoint
* Retrieve specific participant profiles with [Retrieve past participant profile](/team-respondents/retrieve-past-participant-profile)
* Invite multiple past participants directly using [Invite multiple past participants](/team-respondents/invite-multiple-past-participants)
## Audience qualification
Screener responses are qualified across the participant's profile and their actual responses to screener questions to be determined qualified or not. Answering all screener questions with qualifying answers makes them qualified on a screener, but profile qualification can be achieve by matching all filter type audiences features.
Respondent will treat participants that match all audience features with preferential treatment when actively recruiting, but will qualify participants that are not direct matches for signal type audience features.
**Example**
If a participants qualified via the screener AND they match selected `targetAgeGroups` and `targetCountries` but not `targetHouseholdIncome`, their response will be considered qualified by default. Partners or researchers can choose to disqualify these responses to narrow the number of participants and keep recruiting open.
***