Comparison Sites - How do they ensure their prices are up to date?

10,000 + from a number of providers

[Habtom]

How do Comparison Sites like PriceGrabber.com and shopping.com ensure that the prices they get from their providers are uptodate.

For instance, the price of mobile phones seems to change on weekly basis if not daily. How do they keep up with that?

Or there is some kind of "feed" they are getting from the real shops?

Habtom

[edited by: Habtom at 1:57 pm (utc) on Aug. 21, 2007]

[Quadrille]

Most of them use 'real time' information.

If the site is up-to-date, and the set up is right, then the comparison is up-to-date too.

[justgowithit]

Most of them use 'real time' information.

Last I knew most of them relied on user-submitted data-feeds that were often out-dated.

Are you saying that they're spidering merchant sites now? How are they getting real-time data?

[Habtom]

> How are they getting real-time data?
Yea, that is what I wanted to know. Anybody, please enlighten us.

> The second question, how do they really make money? I have a few guesses (commission, sponsored links, featured (still sponsored) items . . . )

Hab

[Marcia]

One way or another they make money by being paid by the vendors they refer people to. Whether it's affiliate commissions or CPM is irrelevant, it's still paid advertising; which is why I can't understand why they're considered to be offering "value" by a certain search engine. It's not unbiased, it's paid for.

[Quadrille]

If they offer a wide enough choice, there is still value for the consumer.

If I'm searching for a book, and they find that Tesco has it cheaper than Amazon - or someone else is a penny more, but post free, then that helps me.

Personally I'd be grateful if they included sites that don't pay commission (I've seen a couple that claim to, but not recently).

Sure it's commercial, it's affiliation too - but so what? they have as much right to exist as, er, Amazon.

I don't think they get any special favors in searches; I often find they don't figure at all for some product searches, while others they seem to do well.

I'm all for the little guy - but we all know that it's impossible to compete head on with the big guy - on the web, or in the mall. Nothing new there ;)

[justgowithit]

They make money from vendors paying per click. I'm surprised you guys haven't used these engines once upon a time. There's no real-time data, it's all user-submitted product feeds that they draw their results from.

It's not unbiased, it's paid for.

Who ever said it was unbiased? All of these engines are out to make a buck. A few years back I was getting decent ROI from a few of them and then they started going down hill. Now I don't use any of them.

[Quadrille]

There's no real-time data, it's all user-submitted product feeds that they draw their results from.

I don't think that's true any more.

The smaller comparison engines rely 100% on submitted feeds, but the OP asked about the biggest of them - they have been spidering for a while, at least for larger clients.

[rayd]

The feed in many cases is dynamic like an rss feed that they query daily.

Or could also be a generated csv file.

[justgowithit]

huh, that's good to know. Of course, I wouldn't be a larger client.

[sun818]

Since shopping comparison is mostly based on price, you would need to negotiate volume with suppliers to have competitive pricing. I tried several of them but dropped them since ROI was dismal for what you had to pay for in clicks. I still like Google Base since ROI has been 100% since day 1.

There's usually section for merchants on these comparison engines to review their service offerings. Many allow you to submit a feed via EDI, XML, or FTP. Not sure where the idea of crawling merchant sites came from, but maybe this is because Froogle at one time would supplement their data feed results with search engine results. It didn't work very well and the search engines results were eventually dropped.

[Easy_Coder]

>>How do they ensure their prices are up to date?

This responsibility lies with the merchants by way of merchant supplied datafeeds.

There are some engines that are crawling but that ones that are like Shopwiki, Google and Become are in the minority. Shopping.com used to crawl for a Fee but I don't know if they still do. Too, you have better control of what data gets used when you build the feed yourself. This is really important with things like GBase Attributes.

My systems ftp fresh data daily to the Comparison Engines to enure the freshness.

[Quadrille]

Thanks for that; That's interesting; I'd thought the number crawling was on the increase.

When you supply your own data, do many have a limited period, after which you drop out? (I know Froogle used to be 28 days).

And is there a 'standard' form for the feed, or do the comparison engines make it up as they go along?

[Easy_Coder]

>>When you supply your own data, do many have a limited period, after which you drop out? (I know Froogle used to be 28 days).
I don't know the answer for this but I'd avoid it by just staying fresh.

>>And is there a 'standard' form for the feed, or do the comparison engines make it up as they go along?
They're all a little different, look for their Datafeed Spec Sheets. Or you can use someone like singlefeed or channel intelligence. Singlefeed will let you supply 1 type of feed and they push it our to all of your partners for you.