fourth is a continuous optimization test. You can use different titles, different ideas, different display site for testing. To see what effect is the best.
is the third competitors. Your data changes, one important reason is the competition ranking, creative change. Remember Zhao Bingquan when it was time to attend a lecture, an entity doing emphasizes the boss. If own turnover has a problem, that is the main reason may be competitors getting better. In the auction, the competition ranking will affect your ranking competition ranking, creative will affect your click rate. Promotion of competitors will affect your conversion rate. So when the data changes, first look at the competition has not changed, and then see if you have a problem. Author Zhao Bingquan, please indicate.