I found this very interesting. I have add a keyword that that was .20 before as the min to activate. When I key in those keywords, I'm the only ad that show. That's pretty nice for .20, but this morning the keyword went up to 1.00, so I search the keyword many times and couldn't find any other ads, there were no ads of the keyword at all. Is the min bid base on the performace of the campaign?
Yes, the minimum bid is based on the CTR of your ads for that specific keyword. If it's been shown many time with a good CTR, your ad will be flagged as non-relevant for that keyword and your minimum bid will be higher.