An ad’s Quality Score on the Display Network will affect:
the Display Network placements on which the ad is eligible to show
the Quality Scores for the keywords in that ad group
whether an ad is eligible to enter the ad auction
the Quality Score for the same ad on Google and the Google Search Network
Explanation:
AdWords uses an ad auction to determine which ads to show, the order those ads will appear, and how much those ads will cost. The Display Network ad auction shares many similarities with the AdWords auction. Your ads are ranked among other advertisers’ ads based on Ad Rank, which is based on your Max CPC bid and Quality Score. This means that, if your Quality Score is sufficiently better than the score of the advertiser immediately below you, you could rank higher than that advertiser, even if this person’s bid is higher than yours.
Read more here: https://support.google.com/adwords/answer/2996564?hl=en&ref_topic=3119129
Cpa score Display
What is the meaning of “cpa score display”.
How to Check a CPA Score Online?
Scores usually come out in the middle of the second month of the window and at the middle of the month during the no-testing period. Generally, most candidates can check scores from the National Association of State Boards of Accountancy (NASBA). If candidates live in state that is not a NASBA state, then NASBA does not release their scores but NASBA will point the candidates to the proper location to check their scores through the same process as checking their scores on NASBA.
https://www.youtube.com/watch?v=0TQIdIKZm8U