Many times I have seen people saying that, Hey CTR models is best for conversion based advertising, & CPM is for BRANDING based advertising.
Sorry, I just don’t agree, It could be vice-versa.
Lets consider this scenario
Here as you can see the avg cost for each click was 0.43$, 7 clicks & boom nearly 31,000 Impressions. Now if you see my average cost for 1000 impressions i.e. CPM is 0.10$.
Now what if you want to pay less & get almost the same results?
Simple, Just change your AD to CPM method, Pay a little less than your current AVG- CPM lets say you set it to 0.05$ ,Wait for a day or so, Now what your really need to do is keep a tab on your CPM ads, See if your bid is still eligible for impressions, If no then increase the bid by CPM BID AVG of, {(your current bid+ Your AVG CPM)/2}
Wait for a day check if you start receiving impressions, If yes, now check is the average CTR that you used to receive earlier is all the same as your current CTR? If the CTR is almost equal or greater than you previous ad , Congratulations!! You just saved some money, How ever if the CTR is poor as compared to your previous ads than you need to rollback to your previous CTR based ad model immediately….
Similarly if let’s say you’re paying on CPM basis, You want maximum impressions, you pay out 1$ for each 1000 impressions, now what you can do is check your current CTR, now with the help of your current CTR you can identify your current CPC. the formula is lets say you bought 50,000 impressions, so your total cost is now 50$, now you are aware that your current CTR is lets say 1%, so we know that you receive lets say about 500 clicks. So your average CPC is now 0.10$. Now waht you can try doing is change your campaigns to CPC based models, now start paying 0.05$ for your clicks. Wait for a day check if your ads are running after lowering down the bids? If yes than great keep a tab on your impressions, check if your ads do get the same exposure in terms of impressions, if the impression count is the same or higher, Congratulations, you just saved upon your CPM, you are paying exactly the half & you have doubled your ROI.
The idea is just to keep a a track on ads & keep on optimizing different ad models, unless you get the maximum of CTR/Impressions & Minimum CPM.
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