Users may arrive at your site from various sources. For example, someone might get there by clicking on an ad, whereas another user clicked on a link from search results or opened a bookmark in their browser. It is important to correctly determine the click source: only sessions that are initiated by clicking on an ad are counted in Yandex.Direct's statistics.
You can select an attribution model in the Report Wizard and the “Search queries” report.
What is an attribution model
An attribution model is a rule that determines which click is the source for a session. Choose from among these models:
First click — whatever source initiated the first click-through to the site within the last 180 days is considered to be the source for any user session within that period. This model lets you track the source for the ad that initially leads a customer to your site and influences all that person's subsequent actions there.
Last click — the session source is considered to be the click that resulted in the user arriving at your site (regardless of their session history). This model may be used for a technical analysis of your site. The Last significant click model is used to analyze how effective your ad campaigns are.
Last significant click — all sources from the last 90 days are nominally divided into significant ones (for example, your ads) and secondary ones (cached pages, internal traffic, or direct traffic to your site). The session source is considered to be a click from an ad. If a session takes place after the user clicks-through from an insignificant source, the session source is still considered to be the last click from an ad. This model allows you to factor conversions in (which is not possible under the Last click model due to the technical restrictions on session duration.
For example, let's say you sell tours to Mars. A user clicked on your ad in the search results and visited your site 10 days ago, but they didn't buy anything. They later visited your site again after clicking on a YAN ad, and then finally ordered a tour package when they visited your site again yesterday from a browser tab that they left open.
Based on the Last click attribution model, the session source would be the click from the open browser tab. If we use the First click model, though, it would be the search ad. Finally, the Last significant click model would list the YAN ad as the source. In this case, the Last significant click model allows you to more accurately determine how effective your ads are in comparison with the Last click model. If a user arrives at your site by clicking on your ad and then leaves a tab with your site open for a long time, then the ad will be considered the correct source of the session.