Comment by cjs_ac | Hacker News Reader

Comment by cjs_ac | Hacker News Reader

> In Calling Bullshit, the authors give the example of the Virginia Mason Quality Equation Q = [Ax(O+S)÷W] (Quality equals Appropriateness times the sum of Outcomes and Service divided by Waste), a formula used for improving operations management in healthcare.

I think it's best to think of this as an overextended metaphor, rather than a clumsy attempt to provide a rigorous relationship. The message to take away from this 'equation' is:

* more appropriateness means more quality; * better outcomes means more quality; * better service means more quality; * less waste means more quality.

It's a small minority of people who give a shit about mathematics. The children who used to whine about, 'When are we every going to use this?' grow up to be adults who complain about not having learnt about how to complete their tax returns at school.

The equation above is an aide de memoire for people managing healthcare facilities. It's irrelevant to people who understand that it's an abuse of mathematical ideas.

The 'Fixing mathiness' section, however, is very good. This article is from a survey company, so this is about increasing the validity of the results you get from their product, but it speaks to the problem of inappropriate statistical methods being used to manufacture signals from noise.

I'd read it as a symptom of something going pretty badly wrong. For example, imagine a funny scenario where a business decides that it needs to use computers to improve efficiency. Some desktop towers are bought. The front-line employees use them as the physical foundation for a new table that they needed and report "mission accomplished" up the chain. The problem in this scenario is that while technically yes, real problems are being solved with the suggested tool someone here is badly, badly out of touch with what needs to be happening to see real improvement.

Similarly here, if there is a formula that stupid being used, even as a memory aid, it suggests to me that real lives could be saved if they embed a few real Ops Research specialists somewhere important instead of whatever they are doing.

>I think it's best to think of this as an overextended metaphor

It may be best, I agree, but it's not what people do. I've seen enough people with advanced degrees take things like FMEA risk priority numbers or adding up the numbers in a Pugh matrix very literally, not as a basis for discussion and insight.

>The children who used to whine about, 'When are we every going to use this?' grow up to be adults who complain about not having learnt about how to complete their tax returns at school.

I've seen my former classmates complain on Facebook about not having been taught things ("there should be a class in high school!") that were absolutely taught in the dumb state required classes.

That equation predicts that great service can outweigh net negative outcomes.

See you wrote it in a clearly understandable way without abusing mathematics or giving any credence to mathematics being involved in the concept.

Only if they are measured on a scale allowing negative values for outcomes and sufficiently high values for service. It would be unsurprising to have outcomes measured from zero and service topping out at 100%. The equation doesn't say anything remotely precise, it's just a bundle of vibes.

> It would be unsurprising to have outcomes measured from zero

Assuming that you can never make anybody worse off than they were before you showed up would be a much worse abuse.

Or you're using a log scale because your effects span many orders of magnitude, or whatever. The specifics are not particularly central to my point beyond that it isn't too hard to wrangle up some scenario where the equation says something completely different.

I'm very skeptical of this view. Additive relationships and multiplicative relationships differ dramatically; the difference is related to linear Vs non linear phenomena. If all you mean is "positively correlated" and "negatively correlated" then you should just say that (or words to that affect).

Exactly this. The equation also fails simple dimensional analysis -- it's nonsense.

I could think of a bunch of simpler ways to state this equation without the baloney false math (similar to the paraphrasing you did).

No, the purpose of putting this into an "equation" is to imply false rigor, and simultaneously to imply that you should hire our people to implement our "healthcare quality framework". I mean, would people really think this is any sort of non-obvious advice if you simply stated, "To improve quality, you should improve appropriateness of treatments, improve outcomes and improve service, and reduce waste." I mean, no shit Sherlock. But once you put it into an "equation", you're deliberately, and falsely, implying "Oooh, science!"

Using an equation to represent this is dishonest. It assumes linearity and proportionality between variables which may not be the case. Also none of the terms are really measurable. You might as well write statements instead.

I mean try defining waste and quality.

Fundamentally, and to use a non-mathematical term appropriately in context, it is a load of bollocks. It is used to make simple ideas look like they are rigorously defined to people without the tools to interpret them. And that is dishonest.

As for inappropriate statistical methods, survey companies are a breeding ground for providing tools which the results of are not interpreted with any statistical rigour or language.

Source: annoyed mathematician.

+1.

One of the few comments on HN i fully agree with without reservation :-)

While folks may use symbols instead of long-winded statements they need to make it clear that it is merely a shorthand and no mathematical rigour is implied.

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