J.D. Powers continues to mislead the public

[roteague]

"Production defects +
Design defects =
IQS defect

I've written before about the limitations of J.D. Power's approach to conducting and reporting reliability. This piece focuses more narrowly on the 2006 Initial Quality Study (IQS), which adds a new wrinkle.

This is the second time the IQS has been redesigned to encompass a larger number of potential issues. Since at least the last redesign, and perhaps before that, the issues included in the study have gone beyond defects that can be fixed to designed-in annoyances that must simply be endured. For example, a few years ago a barely functional cupholder contributed to MINI's poor showing and Hummer's score suffered from complaints about poor fuel economy.

While the 2006 IQS asked about an even larger number of potential design issues, it also provides subscores for "design quality" and "production quality." This is certainly a step in the right direction. Still, an even better strategy would be to separate the two entirely and provide two different stats.

Currently, the two are combined in the overall IQS scores, making it unclear what these scores represent. Aside from having substantially different implications, design quality is far more subjective.

...

The best brand has 0.42 problems per car, while the worst has 1.10, for a best-to-worst difference of 0.68 problems per car. Even much of this narrow range results from a few especially low-scoring brands. The difference between Brand #3 and Brand #35 is 0.41 problems per car. That between Brand #6 and Brand #32 is a scant 0.24 problems per car.

...

It's becoming clearer why J.D. Power lumps design quality into the IQS: without it the absolute differences become very small. And the smaller the differences get, the less people will care about IQS."

http://www.truedelta.com/pieces/IQS2006.php

[Tomko]

I get the sense that with the slimmest of margins between best and worst initial quality the importance of J.D. Power in this regard is eroding. Is J.D. Power, like so many other organizations whose original mandate has evaporated, searching for a way to remain relevant?

If Michael Karesh can achieve critical mass with his True Delta initiative then I think we will find out.

[asim]

Oh gosh...it can get so confusing for us interested in cars, how is everyone else outside the car circle supposed to understand?

[mkaresh]

The hard part is to make stats simple yet valid.

My answer is to direct attention towards the differences between specific cars. Check my demonstration here:

http://www.truedelta.com/report.php

Like it says in ALL CAPS red print at the top of each page, this is just to demonstrate my ideal format. The numbers at this point are not real.

If everyone who has visited my site had signed up to participate, I'd already have a kick-ass sample. But we're getting there, just not so quickly.