“Raising the bid amount” have the least-positive impact. To improve an ad’s perceived quality so it performs better during an ad auction “Raising the bid amount” would have the least-positive impact to an ad’s quality.
If you’re trying such thing, you should focus on other things too. Every time someone does a search that triggers an ad that competes in an auction, we calculate an Ad Rank.
This calculation incorporates your bid and auction-time measurements of expected CTR, ad relevance, and landing page experience, among other factors.
Read more here: https://support.google.com/google-ads/answer/1722122