The above is an article of faith among a certain kind of Web publisher. And some of them are even paying for studies to prove that display ads–basically all the ads you see that aren’t part of search results–really do work on the Web.

Except when they don’t. That’s the unsettling conclusion that some research funded by Yahoo (YHOO) recently reached, the San Francisco Chronicle reports.

The study was produced by the Web giant’s Yahoo Labs, which has been getting new attention in the Carol Bartz regime and beefing up its staff of social scientists by “adding highly credentialed cognitive psychologists, economists and ethnographers from top universities around the world.”

One of the new hires, economics professor David Reiley, tried to track the benefits of a Yahoo ad campaign on behalf of a retail chain. He found that the ads did work, but only for people born before Woodstock:

The research, conducted in partnership with an undisclosed national retailer, sought to accurately measure the impact of Internet display advertising across online and offline sales, by tracking people who had registered with both Yahoo and the store. The research found an approximately 5 percent increase in spending among those who had seen the ads–with 93 percent of those sales occurring in stores.

The potentially worrisome thing, however, was that among those under 40, the percentage was nearly zero. That could reflect the unpopularity of the particular retailer among that demographic. Or it could underscore a growing immunity to display advertising among the Web-savvy younger generation.

Yikes. I asked Yahoo for its take on the study and the company sent me a (not surprisingly) sunnier summary of the research. Some of its highlights:

Major Findings:
By combining a controlled experiment with panel data on purchases, we find statistically and economically significant impacts of advertising on sales.

We estimate the total effect on revenues to be more than eleven times the retailer’s expenditure on advertising during the study.
93% of the effect was on offline (in store) sales.

Persistence: The effects of the campaigns were persistent over time, meaning that the sales impact could be tracked for a period of time after the campaign ended.

Demographics: there was no significant correlation or differences w/r/t location (by state) or gender.

But there was a significant difference w/r/t to age: customers over the age of 40 were significantly more responsive to the ads in terms of sales. The largest effect came from senior citizens (65+).

Clicks versus non-Clicks: Though clicks are a standard measure of performance in online-advertising, we find that online advertising has substantial effects on those who merely view but do not click the ads.

We find that 78% of the effect in sales comes from those who view ads but do not click them, while only 22% can be attributed to those who click.

Count me among the group disposed to think that brand ads on the Web do work, by the way. But then again, I have a vested interest in this being true since it’s what’s supposed to keep me clothed and fed. I’d hate to see scientific proof that it’s all a pipe dream.

For a contrary perspective, funded by people whose interests align with mine, check out this study funded by the Online Publishers Association.

[Image credit: pedrosimoes7]

The deal is an obvious coup for the big-box retailer, which, with the exception of Apple (AAPL) and AT&T (T), has a national exclusive on the device through Christmas. Just a few weeks back, Stifel Nicolaus analyst David Schick suggested that availability of the iPhone only at Apple and AT&T Wireless stores could “hurt demand or at least foot traffic to Best Buy and Circuit City.” Now that appears to be the fate of Circuit City (CC) alone.

“It solidifies us as the place to go for the cool stuff,” Best Buy Mobile President Shawn Score told Reuters. “Our customers are looking for this product. We do believe that broadening our assortment and having iPhone in our stores is certainly going to be very important [heading into the holiday season].”

Important for Apple as well, assuming the company works through its iPhone shortage problems. Offering the device for sale in Best Buy’s (BBY) 970 stores will certainly make it quite a bit easier for Apple to reach its oft-stated goal of selling 10 million iPhones in 2008. Not that it really needs any help in that department. According to Piper Jaffray analyst Gene Munster Apple is on track to sell 4.47 million iPhones in this quarter alone.

The deal is an obvious coup for the big-box retailer, which, with the exception of Apple (AAPL) and AT&T (T), has a national exclusive on the device through Christmas. Just a few weeks back, Stifel Nicolaus analyst David Schick suggested that availability of the iPhone only at Apple and AT&T Wireless stores could “hurt demand or at least foot traffic to Best Buy and Circuit City.” Now that appears to be the fate of Circuit City (CC) alone.

“It solidifies us as the place to go for the cool stuff,” Best Buy Mobile President Shawn Score told Reuters. “Our customers are looking for this product. We do believe that broadening our assortment and having iPhone in our stores is certainly going to be very important [heading into the holiday season].”

Important for Apple as well, assuming the company works through its iPhone shortage problems. Offering the device for sale in Best Buy’s (BBY) 970 stores will certainly make it quite a bit easier for Apple to reach its oft-stated goal of selling 10 million iPhones in 2008. Not that it really needs any help in that department. According to Piper Jaffray analyst Gene Munster Apple is on track to sell 4.47 million iPhones in this quarter alone.