Attribution
Paid search
Also called SEM, PPC search.
Paid search is visits from ads on a search results page, identified by a tag or an auto-tag. You pay per click.
How it is measured
Ad links carry a tag or an auto-appended click id, and the analytics tool labels these sessions as paid search with a medium such as cpc. Spend and clicks come from the ad platform.
Make sure the ad platform's click count is close to the sessions in analytics. A gap of more than a fifth can mean broken landing pages or dropped tags.
Worked example
A dental implant clinic spends $3,000 in a month and the ad platform reports 1,240 clicks. Analytics shows only 880 paid sessions.
The clinic finds the landing page takes five seconds to load on mobile and many visitors leave before the tag fires. After a speed fix, sessions rise to 1,150 and booked consultations go from 11 to 19.
How it differs
Paid search is bought and tagged. Organic search is earned and untagged. Paid clicks cost money, and both can appear for the same query.
Common errors
Leaving ads untagged. Judging only by clicks. Forgetting that slow pages lose the session. Paying for brand terms that organic would catch. Not matching platform and analytics conversions.
In practice
Compare click counts with sessions. Fix pages where the gap is largest. Check conversions in both the ad platform and analytics and note the difference.