i was getting very low traffic then i change my ads placement on technology blog.and i get lot of traffic in just 1 hour.i put my ads also in post near title
Yes, but you wasn't talking about earning, you talked about traffic. The ad placement may affect your traffic long-term, that is, if you irritate the visitors, but not overnight.
Earnings are definitely directly related to ad placement. Having ads placed properly on page can make a HUGE difference from an epc or ecpm standpoint. If you are interested in beta testing a new type of ad network, check out the link in my footer. You will need an invitation code: VE0XOSZZSTFY1Z
Its no use of changing the ad, Just try to put up your ad in top most PR6-9 websites.. you can automatically see the traffic within an hour for long term basis..