Sponsor stats Vs adserver stats
 

Sorry, this is probably going to be a stupid question, but I started promoting an affiliate three days ago on CalModels and the banner is being tracked by phpAdsNew (which I have been using for ages and know works and is accurate)...

My phpAdsNew stats for that banner for the first two days shows 37 clicks, but the sponsors stats page only shows 21... this seemed kinda odd to me...

Being a noob.. is this common/happen a lot/is expected? Its possible maybe they are having some issues with their stats system... dunno...

There could be many explanations. The most likely is the sponsor tracks uniques and some of your referrals were already sent there by someone else.

If they show RAW then your numbers should be close.

the sponsor might only count unique hits or second page hits

yeah, but their statistics page shows columns of raw, unique, join etc and it says 21 raw... maybe they had a problem with their stats software or something...

Well, that's simple to answer. Internet Voodoo. That's why I have sales on days when I only send three hits and it's the reason why my sales seem to come from pages that haven't been tracked by the sponsor's stats.

Some sponsors - although they list clicks as "uniques" - really arent counting the first page hits - they are counting how many people click "next" or "2nd page"
I have one sponsor that I know I am sending around 300 uniques to from one banner - and they are reporting 15 uniques a day or so - other sponsors will report uniques only if the page loads completely on their site etc - way too many variables :)