This really looks like a bull attack against VGChartz,is not the first time,but coming from a "respectable site" this looks awful.

Anyway,for a low incoming site,the VGC's research is one of the best,if somebody wants to argue about this then simply don't come to the site and follow the NPD's numbers,

It's a free world and if someone gets mad with VGChartz they can skip it.

a 10% error, let alone 20%,  is a mortal flaw in methodology. Any professional outlet that often possesses that terrible margin of error wouldn't last long in the business world.

The article didn't say much I didn't already know, and I agree completely with it.

To Brett Walton: Please give credit to your sources, that's the way it should be.

Wow, I can't believe some of you guys, ioi is doing a great job with this site. You should be thanking him instead of making stupid posts.

Read this post from naznatips:

"That said, all data trackers provide nothing but estimates. ALL. Famitsu and Media Create differ as much as 40% on a given week, and each one tracks more of the Japanese market than NPD tracks of the NA market. Pretending any sales data gives anything more than a basic idea of sales trends is laughable."

Famitsu and Media Create are profesional tracking services.  I guess they and the NPD are all mortally flawed by your standards.

This is not science, and it is not a labratory.  There are different standards in the real world.

one thing to add to this, NPD doesn't get Amazon, Walmart, Best Buy, and I believe Target's sales data.  And they are 4 of the, if not thee, biggest retailers in America so all anyone can do is make an educated guess and even though ioi doesn't get nearly the data npd does, his numbers are within reasonable margins on most games of the "all mighty" npd's data.

to be a free site its pretty good.. but that news about the european data is new to me

Tell that to Pachter. A recent issue of EGM had a piece on him and his job in which he openly discussed his mistakes(that he reported to paying clients). It's all part of how things work, the same thing goes for us here sometimes. What about all of the professional analysts and industry insiders who stated the Wii would come in third place and that the PS3 would come out of the gate with guns blazing? Surely you don't expect VGC to be the one entity immune to mistakes...

Are you at all familiar with Media Create and Famitsu's differences in data? Should they just draw straws to see who is the standard and have the other close it's doors?

And since you made a news channel analogy, I'll make my own. What about when all of the networks were reporting that Gore had clinched the presidency over Bush? That was a pretty big flub concerning the presidency of the United States, it doesn't get much bigger than that in the news. Poodoo happens and they learned from their mistake. If the major sources for news in America can screw up something like that and keep their integrity, VGC shouldn't be thrown under the bus every time something is out of order.

Of course we all want a larger sample for data and we all know the NPD has the largest for America. What irks me is that so many people are acting like ioi only wants to operate on a 2-3% sample of the market. If it was so easy to get retailers onboard, I'd think the mighty NPD would be able to have more than 60% market coverage.

Of course, the real issue that groups like NPD and MediaCrate have with VG Chartz is that they've disrupted their industry. Sure, VG Chartz isn't as accurate, but it's also free and updated weekly instead of monthly. And it has built-in tools to gauge how well products have done compared to each other in a huge number of ways, something that I don't think any other tracking firm offers (let alone at no cost to the user). Most people will gladly take more frequent but less accurate updates that are free over less frequent updates that somebody has to pay for that are more accurate. We want the sales figures to speculate on, not picture-perfect accuracy of them. That'd be nice, but it's not as important as having the data itself.

 Dialmydrive is paranoid. That is all I can say :). 

 Any reason you singled out Just_Ben instead of other poster who also criticize ioi ? And what is the relationship between respect and critic ? Just because my son respect me, I didn't expect him to became yes-man, and never criticize me, even when I am wrong.