Comments on: How economists get tripped up by statistics A slice of lime in the soda Sun, 26 Oct 2014 19:05:02 +0000 hourly 1 By: Scartaris Fri, 03 Aug 2012 13:45:35 +0000 Ah, I get it now, thanks!

By: VectorPosse Thu, 02 Aug 2012 19:51:17 +0000 @Scartaris: Since the goal is to get the dot above the x-axis, they are are using a one-sided interval. The 95th percentile is at 1.645, so that’s the critical value in this case. (For a two-sided interval 1.645 corresponds to a 90% confidence interval. That makes sense: 90% removes 5% from each tail, and so the upper bound is at the 95th percentile.)

By: Scartaris Thu, 02 Aug 2012 11:42:20 +0000 I’ve just had a look at the paper, and it does not seem to me that 47 is the correct answer, based on the statistics presented in the paper. The reason the authors obtain 47 is that they use 1.645 as the z value for the 95% confidence interval. However, the correct value is 1.96 (cf. viation#Rules_for_normally_distributed_d ata ). This means that the correct value for X would be 56.

Unless there’s something I’ve missed?

By: kcl4s Sat, 14 Jul 2012 07:58:19 +0000 Generalizing this study to doctors and/or other social scientists is bad social science. In my opinion, the issue isn’t just the misuse of statistics but the misuse of the scientific method.

By: soyerian Fri, 13 Jul 2012 10:32:49 +0000 Hello,

We are Emre and Robin, the authors of the study featured in this post.

We would like thank Mr. Salmon for his insightful discussion of the study and all the commentators for their remarks.

This study is now a discussion paper in International Journal of Forecasting. Hence, we would like to contribute to the ongoing discussion by posting links to the comments made on the study and our reply to those comments.

Due to copyright issues, we cannot share freely the journal versions, but can put links to the last working papers.

Here is the study: Soyer%20%26%20Hogarth_2012.pdf

Here is the comment paper by Scott Armstrong: s/?whdmsaction=public:main.file&fileID=1 929

Here is the comment paper by Stephen Ziliak: bstract_id=2104279

Here is the comment paper by Nassim Taleb and Daniel Goldstein: bstract_id=1941792

Here is the comment paper by Keith Ord: bstract_id=2016195

Here is our reply to the comments: Response_by_Soyer_Hogarth_2012.pdf

Thank you once more for the engaging discussion.

Best wishes,

Emre and Robin

By: SamuelReich Thu, 12 Jul 2012 02:20:41 +0000 Now you why better engineers look down on liberal arts types. We want facts not guess. Statistics is the core of economic data for decisions, but for got it.

I worked with engineers who got rid of their text books long ago and wanted to get by with smile. Lots of them said “You cannot do that” (calculate the results).

Of cause when money is involved statistics can be rigged.

By: QCIC Wed, 11 Jul 2012 19:07:54 +0000 These results do not surprise me when you see a lot of the posts professional economists make online. They are as a whole bright, but not exactly world beaters.

By: AaronX.Situ Wed, 11 Jul 2012 16:58:07 +0000 This is similar to what Steven Levitt talked about in his book “Freakanomics”, where criminologists thought that better policing and increase number of officers were the main contributor to the fall of crime rate, but they didn’t look deeper and figure out that it was because of the legalization of abortion.

By: dsude Wed, 11 Jul 2012 03:55:07 +0000 To me, this underscores the importance of presenting results (to the public and to oneself) in a manner that reflects the underlying assumptions of the model and the underlying point of the model’s results. It takes time, and cognitive resources, to go from reading someone’s results to understanding patterns in someone’s data. The process can be made more efficient by using graphs or even having a mental checklist – did I think about what this effect size means? Did I think about variance in the model? The quantified error? In the end, though, the process simply shouldn’t be rushed, and if you do rush, you should have a certain skepticism about the quality of your interpretations.

By: sisyphus1 Wed, 11 Jul 2012 03:10:07 +0000 thanks Felix – is there a link to the paper?
it would be very interesting to see the distribution of answers for each question (e.g. if the distribution of answers is clearly bimodal, then it might indicate a misinterpretation of the question)