Research Topics:

Media Research-General | Media Research-Radio | Media Research-Television

Industry/Market Focus:

Advertising Agencies

Content Type:

Glossary

ADI (Area of Dominant Influence) Definition

A television market, as defined by TV audience measurement firm Arbitron. Each ADI is assigned Arbitron's three-digit numeric code.

ADIs give marketing researchers a common, behavior-based framework for analyzing audiences, planning ad buys and comparing regional performance. Without them, measurement would be fragmented and harder to standardize.

Why are ADIs important and helpful to marketing researchers?

Defining the market

• ADIs provide a standardized geographic unit for analyzing media markets.

• Each county belongs to exactly one ADI, so researchers can cleanly compare markets without overlap.

• This gives marketing researchers a consistent “map” of media consumption across the U.S.

Media planning and buying

• Advertisers use ADIs to determine where to place TV or radio ads for maximum impact.

• If a brand wants to dominate in a region (say Minneapolis-St. Paul), the ADI boundary ensures they’re buying into the correct audience area.

• Researchers help advertisers link local consumption data to specific ADIs, which informs ad spend.

Audience measurement and targeting

• ADIs are built on actual viewing/listening behaviors, so they reflect real audience influence, not just political or geographic borders.
• This helps researchers target messages more precisely based on media dominance, rather than just broad census regions.

Comparative analysis across markets

• Marketing researchers can use ADIs to:
  • Compare media penetration (e.g., how a network performs in Chicago ADI vs. Milwaukee ADI).
  • Assess brand awareness or usage differences by market.
  • Identify strong vs. weak markets for a product launch or campaign.

Segmentation and strategy

• ADIs allow researchers to overlay demographics, psychographics or purchasing data with media markets.
• Example: If a detergent brand over-indexes in the Atlanta ADI but under-indexes in Dallas ADI, researchers can investigate why (media mix, demographics, competitor strength).

Tracking change over time

• Since ADIs are updated based on changing media patterns, researchers can see how media influence shifts across regions.
• This is useful for spotting emerging growth markets or declines in traditional media dominance.