Quality score dynamics can vary between different advertisers and PPC markets

In an earlier post, it shown that the relationship between CTR and position can vary for different advertisers, especially in the higher positions.   These differences can potentially be explained by differences in brand traffic or are real differences in the click-through related to the dynamics of geographical PPC markets or the nature of the advertiser’s business.  It is interesting to note that the CTR in the higher positions seem to be considerably better for advertisers in less mature online markets namely Australia and South Africa.   We investigated this further by only focusing on non-brand specific keywords.  To achieve this we included a factor indicating the brand or non-brand status of keywords in our model. Figure 1 compares the four advertisers on all non-brand keywords with a QS of 7.   Even after non-brand differentiation we continue to observe substantially higher CTR in the top positions for Australian and South African advertisers compared to their UK & US counterparts used in the same model. This could be reflective of a lower level of competition relative to more developed markets resulting in a smaller number of competitive ads on a search results page, which in turn drives higher click-through in top positions. From this it is also clear that there are no fixed thresholds for determining quality score, rather it is determined on the relative CTR which varies across advertisers and potentially also  geographical regions

Figure 1: CTR by position across four advertisers for all non-brand keywords with a quality score of 7.