Blog: Want to Know If Someone Is Manipulating Data? - Milton Packer describes how to distinguish science from magic

https://www.medpagetoday.com/blogs/revolutionandrevelation/78239

 

Surely we already know the WHOLE WORLD is a stage?

 

For anyone interested in how data from trials can be manipulated and distorted, this book is brilliant and well worth the effort of reading it :

 

How familiar that sounds.

 

When I saw the title of this thread, it brought to mind the fascinating Benford's law, which states that in any genuine set of data, if you count up all the numbers, you should find around 30% of those numbers being with a "1", and not around 11% as you might expect.

However, in a fake set of data, you will get around 11%. So that's one way to detect whether accountants or researchers have faked their figures.

 

Not always. From the wikipedia page

So it depends on the nature of the data your dodgy accountants/researchers are presenting.

 

Sure, but when the data falls into a normal distribution, which a lot of real-life data does, then Benford's law applies.

Of course if you are a dodgy accountant who knows about Benford's law, then you can actually generate fake data (ie, have 30% of numbers start with 1) which will pass the Benford test.

 

Wikipedia (and that is the limit of my knowledge about this) seems to be saying that it is not whether or not the distribution is normal but how wide it is. If it's width covers several orders of magnitude, Benford's law applies, but if it is narrow so only covers one order of magnitude then it doesn't. An example given of a distribution where it does not apply is human heights, which is a normal distribution.

For example, if human heights are measured in feet, heights that start with a "1" are likely to be rather rare, definitely not 30%.

 

That makes more sense.

From memory, I thought Benford's law would always apply when you have a normal distribution, but maybe I got that wrong (it was decades ago that I read about Benford's law).