In recognition of Fisher’s birthday (Feb 17), I reblog what I call the “Triad”–an exchange between Fisher, Neyman and Pearson (N-P) a full 20 years after the Fisher-Neyman break-up–adding a few new introductory remarks here. While my favorite is still the reply by E.S. Pearson, which alone should have shattered Fisher’s allegations that N-P “reinterpret” tests of significance as “some kind of acceptance procedure”, they are all chock full of gems for different reasons. They are short and worth rereading. Neyman’s article pulls back the cover on what is really behind Fisher’s over-the-top polemics, what with Russian 5-year plans and commercialism in the U.S. Not only is Fisher jealous that N-P tests came to overshadow “his” tests, he is furious at Neyman for driving home the fact that Fisher’s fiducial approach had been shown to be inconsistent (by others). The flaw is glaring and is illustrated very simply by Neyman in his portion of the triad. Further details may be found in my book, SIST (2018) especially pp 388-392 linked to here. It speaks to a common fallacy seen every day in interpreting confidence intervals. As for Neyman’s “behaviorism”, Pearson’s last sentence is revealing. Continue reading

# E.S. Pearson

## R.A. Fisher: “Statistical methods and Scientific Induction” with replies by Neyman and E.S. Pearson

## Performance or Probativeness? E.S. Pearson’s Statistical Philosophy: Belated Birthday Wish

This is a belated birthday post for E.S. Pearson (11 August 1895-12 June, 1980). It’s basically a post from 2012 which concerns an issue of interpretation (long-run performance vs probativeness) that’s badly confused these days. Yes, i know I’ve been neglecting this blog as of late, but this topic will appear in a new guise in a post I’m writing now, to appear tomorrow.

**HAPPY BELATED BIRTHDAY EGON!**

Are methods based on error probabilities of use mainly to supply procedures which will not err too frequently in some long run? (*performance*). Or is it the other way round: that the control of long run error properties are of crucial importance for probing the causes of the data at hand? (*probativeness*). I say no to the former and yes to the latter. This, I think, was also the view of Egon Sharpe (E.S.) Pearson. Continue reading

## R.A. Fisher: “Statistical methods and Scientific Induction” with replies by Neyman and E.S. Pearson

In Recognition of Fisher’s birthday (Feb 17), I reblog his contribution to the “Triad”–an exchange between Fisher, Neyman and Pearson 20 years after the Fisher-Neyman break-up. The other two are below. My favorite is the reply by E.S. Pearson, but all are chock full of gems for different reasons. They are each very short and are worth your rereading. Continue reading

## Performance or Probativeness? E.S. Pearson’s Statistical Philosophy: Belated Birthday Wish

This is a belated birthday post for E.S. Pearson (11 August 1895-12 June, 1980). It’s basically a post from 2012 which concerns an issue of interpretation (long-run performance vs probativeness) that’s badly confused these days. I’ll post some Pearson items this week to mark his birthday.

**HAPPY BELATED BIRTHDAY EGON!**

Are methods based on error probabilities of use mainly to supply procedures which will not err too frequently in some long run? (*performance*). Or is it the other way round: that the control of long run error properties are of crucial importance for probing the causes of the data at hand? (*probativeness*). I say no to the former and yes to the latter. This, I think, was also the view of Egon Sharpe (E.S.) Pearson.

*Cases of Type A and Type B*

“How far then, can one go in giving precision to a philosophy of statistical inference?” (Pearson 1947, 172)

Pearson considers the rationale that might be given to N-P tests in two types of cases, A and B:

“(A) At one extreme we have the case where repeated decisions must be made on results obtained from some routine procedure…

(B) At the other is the situation where statistical tools are applied to an isolated investigation of considerable importance…?” (ibid., 170)

## Jerzy Neyman and “Les Miserables Citations” (statistical theater in honor of his birthday yesterday)

**My second Jerzy Neyman item, in honor of his birthday, is a little play that I wrote for**** Statistical Inference as Severe Testing: How to Get Beyond the Statistics Wars (****2018):**

**A local acting group is putting on a short theater production based on a screenplay I wrote: “Les Miserables Citations” (“Those Miserable Quotes”) [1]. The “miserable” citations are those everyone loves to cite, from their early joint 1933 paper:**

We are inclined to think that as far as a particular hypothesis is concerned, no test based upon the theory of probability can by itself provide any valuable evidence of the truth or falsehood of that hypothesis.

But we may look at the purpose of tests from another viewpoint. Without hoping to know whether each separate hypothesis is true or false, we may search for rules to govern our behavior with regard to them, in following which we insure that, in the long run of experience, we shall not be too often wrong. (Neyman and Pearson 1933, pp. 290-1).

## R.A. Fisher: “Statistical methods and Scientific Induction”

In Recognition of Fisher’s birthday (Feb 17), I reblog his contribution to the “Triad”–an exchange between Fisher, Neyman and Pearson 20 years after the Fisher-Neyman break-up. The other two are below. They are each very short and are worth your rereading.

*“Statistical Methods and Scientific Induction“*

*by Sir Ronald Fisher (1955)
*

**SUMMARY**

The attempt to reinterpret the common tests of significance used in scientific research as though they constituted some kind of acceptance procedure and led to “decisions” in Wald’s sense, originated in several misapprehensions and has led, apparently, to several more.

The three phrases examined here, with a view to elucidating they fallacies they embody, are:

- “Repeated sampling from the same population”,
- Errors of the “second kind”,
- “Inductive behavior”.

Mathematicians without personal contact with the Natural Sciences have often been misled by such phrases. The errors to which they lead are not only numerical.

To continue reading Fisher’s paper.

**“Note on an Article by Sir Ronald Fisher“**

**by Jerzy Neyman (1956)**

**Summary**

(1) FISHER’S allegation that, contrary to some passages in the introduction and on the cover of the book by Wald, this book does not really deal with experimental design is unfounded. In actual fact, the book is permeated with problems of experimentation. (2) Without consideration of hypotheses alternative to the one under test and without the study of probabilities of the two kinds, no purely probabilistic theory of tests is possible. Continue reading

## Neyman-Pearson Tests: An Episode in Anglo-Polish Collaboration: Excerpt from Excursion 3 (3.2)

**3.2 N-P Tests: An Episode in Anglo-Polish Collaboration***

We proceed by setting up a specific hypothesis to test,

H_{0 }in Neyman’s and my terminology, the null hypothesis in R. A. Fisher’s . . . in choosing the test, we take into account alternatives toH_{0 }which we believe possible or at any rate consider it most important to be on the look out for . . .Three steps in constructing the test may be defined:

Step 1. We must first specify the set of results . . .

Step 2.We then divide this set by a system of ordered boundaries . . .such that as we pass across one boundary and proceed to the next, we come to a class of results which makes us more and more inclined, on the information available, to reject the hypothesis tested in favour of alternatives which differ from it by increasing amounts.

Step 3. We then, if possible, associate with each contour level the chance that, ifH_{0}is true, a result will occur in random sampling lying beyond that level . . .In our first papers [in 1928] we suggested that the likelihood ratio criterion, λ, was a very useful one . . . Thus Step 2 proceeded Step 3. In later papers [1933–1938] we started with a fixed value for the chance, ε, of Step 3 . . . However, although the mathematical procedure may put Step 3 before 2, we cannot put this into operation before we have decided, under Step 2, on the guiding principle to be used in choosing the contour system. That is why I have numbered the steps in this order. (Egon Pearson 1947, p. 173)

In addition to Pearson’s 1947 paper, the museum follows his account in “The Neyman–Pearson Story: 1926–34” (Pearson 1970). The subtitle is “Historical Sidelights on an Episode in Anglo-Polish Collaboration”!

We meet Jerzy Neyman at the point he’s sent to have his work sized up by Karl Pearson at University College in 1925/26. Neyman wasn’t that impressed: Continue reading

## A. Spanos: Egon Pearson’s Neglected Contributions to Statistics

*Continuing with the discussion of E.S. Pearson in honor of his birthday:*

**Egon Pearson’s Neglected Contributions to Statistics**

by** Aris Spanos**

**Egon Pearson** (11 August 1895 – 12 June 1980), is widely known today for his contribution in recasting of Fisher’s significance testing into the * Neyman-Pearson (1933) theory of hypothesis testing*. Occasionally, he is also credited with contributions in promoting statistical methods in industry and in the history of modern statistics; see Bartlett (1981). What is rarely mentioned is Egon’s early pioneering work on:

**(i) specification**: the need to state explicitly the inductive premises of one’s inferences,

**(ii) robustness**: evaluating the ‘sensitivity’ of inferential procedures to departures from the Normality assumption, as well as

**(iii) Mis-Specification (M-S) testing**: probing for potential departures from the Normality assumption.

Arguably, modern frequentist inference began with the development of various finite sample inference procedures, initially by William Gosset (1908) [of the **Student’s t** fame] and then **Fisher** (1915, 1921, 1922a-b). These inference procedures revolved around a particular statistical model, known today as *the simple Normal model*: Continue reading

## R.A. Fisher: “Statistical methods and Scientific Induction”

I continue a week of Fisherian posts begun on his birthday (Feb 17). This is his contribution to the “Triad”–an exchange between Fisher, Neyman and Pearson 20 years after the Fisher-Neyman break-up. The other two are below. They are each very short and are worth your rereading.

*“Statistical Methods and Scientific Induction”*

*by Sir Ronald Fisher (1955)
*

**SUMMARY**

The attempt to reinterpret the common tests of significance used in scientific research as though they constituted some kind of acceptance procedure and led to “decisions” in Wald’s sense, originated in several misapprehensions and has led, apparently, to several more.

The three phrases examined here, with a view to elucidating they fallacies they embody, are:

- “Repeated sampling from the same population”,
- Errors of the “second kind”,
- “Inductive behavior”.

Mathematicians without personal contact with the Natural Sciences have often been misled by such phrases. The errors to which they lead are not only numerical.

To continue reading Fisher’s paper.

**“Note on an Article by Sir Ronald Fisher“**

**by Jerzy Neyman (1956)**

**Summary**

(1) FISHER’S allegation that, contrary to some passages in the introduction and on the cover of the book by Wald, this book does not really deal with experimental design is unfounded. In actual fact, the book is permeated with problems of experimentation. (2) Without consideration of hypotheses alternative to the one under test and without the study of probabilities of the two kinds, no purely probabilistic theory of tests is possible. (3) The conceptual fallacy of the notion of fiducial distribution rests upon the lack of recognition that valid probability statements about random variables usually cease to be valid if the random variables are replaced by their particular values. The notorious multitude of “paradoxes” of fiducial theory is a consequence of this oversight. (4) The idea of a “cost function for faulty judgments” appears to be due to Laplace, followed by Gauss.

“**Statistical Concepts in Their Relation to Reality“.**

**by E.S. Pearson (1955)**

Controversies in the field of mathematical statistics seem largely to have arisen because statisticians have been unable to agree upon how theory is to provide, in terms of probability statements, the numerical measures most helpful to those who have to draw conclusions from observational data. We are concerned here with the ways in which mathematical theory may be put, as it were, into gear with the common processes of rational thought, and there seems no reason to suppose that there is one best way in which this can be done. If, therefore, Sir Ronald Fisher recapitulates and enlarges on his views upon statistical methods and scientific induction we can all only be grateful, but when he takes this opportunity to criticize the work of others through misapprehension of their views as he has done in his recent contribution to this *Journal* (Fisher 1955 “Scientific Methods and Scientific Induction” ), it is impossible to leave him altogether unanswered.

In the first place it seems unfortunate that much of Fisher’s criticism of Neyman and Pearson’s approach to the testing of statistical hypotheses should be built upon a “penetrating observation” ascribed to Professor G.A. Barnard, the assumption involved in which happens to be historically incorrect. There was no question of a difference in point of view having “originated” when Neyman “reinterpreted” Fisher’s early work on tests of significance “in terms of that technological and commercial apparatus which is known as an acceptance procedure”. There was no sudden descent upon British soil of Russian ideas regarding the function of science in relation to technology and to five-year plans. It was really much simpler–or worse. *The original heresy, as we shall see, was a Pearson one!…*

To continue reading, “Statistical Concepts in Their Relation to Reality” click HERE

## A. Spanos: Egon Pearson’s Neglected Contributions to Statistics

*Continuing with my Egon Pearson posts in honor of his birthday, I reblog a post by Aris Spanos: ** “**Egon Pearson’s Neglected Contributions to Statistics“. *

**Egon Pearson** (11 August 1895 – 12 June 1980), is widely known today for his contribution in recasting of Fisher’s significance testing into the * Neyman-Pearson (1933) theory of hypothesis testing*. Occasionally, he is also credited with contributions in promoting statistical methods in industry and in the history of modern statistics; see Bartlett (1981). What is rarely mentioned is Egon’s early pioneering work on:

**(i) specification**: the need to state explicitly the inductive premises of one’s inferences,

**(ii) robustness**: evaluating the ‘sensitivity’ of inferential procedures to departures from the Normality assumption, as well as

**(iii) Mis-Specification (M-S) testing**: probing for potential departures from the Normality assumption.

Arguably, modern frequentist inference began with the development of various finite sample inference procedures, initially by William Gosset (1908) [of the **Student’s t** fame] and then **Fisher** (1915, 1921, 1922a-b). These inference procedures revolved around a particular statistical model, known today as *the simple Normal model*: Continue reading

## Performance or Probativeness? E.S. Pearson’s Statistical Philosophy

E.S. Pearson died on this day in 1980. Aside from being co-developer of Neyman-Pearson statistics, Pearson was interested in philosophical aspects of statistical inference. A question he asked is this: Are methods with good error probabilities of use mainly to supply procedures which will not err too frequently in some long run? (*performance*). Or is it the other way round: that the control of long run error properties are of crucial importance for probing the causes of the data at hand? (*probativeness*). I say no to the former and yes to the latter. But how exactly does it work? It’s not just the frequentist error statistician who faces this question, but also some contemporary Bayesians who aver that the performance or calibration of their methods supplies an evidential (or inferential or epistemic) justification (e.g., Robert Kass 2011). The latter generally ties the reliability of the method that produces the particular inference C to degrees of belief in C. The inference takes the form of a probabilism, e.g., Pr(C|x), equated, presumably, to the reliability (or coverage probability) of the method. But why? The frequentist inference is C, which is qualified by the reliability of the method, but there’s no posterior assigned C. Again, what’s the rationale? I think existing answers (from both tribes) come up short in non-trivial ways. Continue reading

## Jerzy Neyman and “Les Miserables Citations” (statistical theater in honor of his birthday)

**For my final Jerzy Neyman item, here’s the post I wrote for his birthday last year: **

**A local acting group is putting on a short theater production based on a screenplay I wrote: “Les Miserables Citations” (“Those Miserable Quotes”) [1]. The “miserable” citations are those everyone loves to cite, from their early joint 1933 paper:**

We are inclined to think that as far as a particular hypothesis is concerned, no test based upon the theory of probability can by itself provide any valuable evidence of the truth or falsehood of that hypothesis.

But we may look at the purpose of tests from another viewpoint. Without hoping to know whether each separate hypothesis is true or false, we may search for rules to govern our behavior with regard to them, in following which we insure that, in the long run of experience, we shall not be too often wrong. (Neyman and Pearson 1933, pp. 290-1).

In this early paper, Neyman and Pearson were still groping toward the basic concepts of tests–for example, “power” had yet to be coined. Taken out of context, these quotes have led to knee-jerk (behavioristic) interpretations which neither Neyman nor Pearson would have accepted. What was the real context of those passages? Well, the paper opens, just five paragraphs earlier, with a discussion of a debate between two French probabilists—Joseph Bertrand, author of “Calculus of Probabilities” (1907), and Emile Borel, author of “Le Hasard” (1914)! According to Neyman, what served* “as an inspiration to Egon S. Pearson and myself in our effort to build a frequentist theory of testing hypotheses”(1977, p. 103) *initially grew out of remarks of Borel, whose lectures Neyman had attended in Paris. He returns to the Bertrand-Borel debate in four different papers, and circles back to it often in his talks with his biographer, Constance Reid. His student Erich Lehmann (1993), regarded as the authority on Neyman, wrote an entire paper on the topic: “The Bertrand-Borel Debate and the Origins of the Neyman Pearson Theory”. Continue reading

## History of statistics sleuths out there? “Ideas came into my head as I sat on a gate overlooking an experimental blackcurrant plot”–No wait, it was apples, probably

Here you see my scruffy sketch of Egon drawn 20 years ago for the frontispiece of my book, “Error and the Growth of Experimental Knowledge” (EGEK 1996). The caption is

“I might recall how certain early ideas came into my head as I sat on a gate overlooking an experimental blackcurrant plot…–E.S Pearson, “Statistical Concepts in Their Relation to Reality”.

He is responding to Fisher to “dispel the picture of the Russian technological bogey”. [i]

So, as I said in my last post, just to make a short story long, I’ve recently been scouring around the history and statistical philosophies of Neyman, Pearson and Fisher for purposes of a book soon to be completed, and I discovered a funny little error about this quote. Only maybe 3 or 4 people alive would care, but maybe someone out there knows the real truth.

OK, so I’d been rereading Constance Reid’s great biography of Neyman, and in one place she interviews Egon about the sources of inspiration for their work. Here’s what Egon tells her: Continue reading

## Jerzy Neyman and “Les Miserables Citations” (statistical theater in honor of his birthday)

**In honor of Jerzy Neyman’s birthday today, a local acting group is putting on a short theater production based on a screenplay I wrote: “Les Miserables Citations” (“Those Miserable Quotes”) [1]. The “miserable” citations are those everyone loves to cite, from their early joint 1933 paper:**

We are inclined to think that as far as a particular hypothesis is concerned, no test based upon the theory of probability can by itself provide any valuable evidence of the truth or falsehood of that hypothesis.

But we may look at the purpose of tests from another viewpoint. Without hoping to know whether each separate hypothesis is true or false, we may search for rules to govern our behavior with regard to them, in following which we insure that, in the long run of experience, we shall not be too often wrong. (Neyman and Pearson 1933, pp. 290-1).