**van Belle book**

Note an entire book: _Statistical Rules of Thumb_ by Gerald van Belle. 

https://onlinelibrary.wiley.com/doi/book/10.1002/9780470377963

I guess anybody with experience would rate some of van Belle's rules as bang on and some as misguided or beyond their personal experience; and that would apply too to anybody else's book. 

**Parker book**

I like this book from some years back. 

Parker, Tom. 1988. _Rules of Thumb._ Wellingborough: Equation. 


I have selected some of its rules that seem to apply either to statistically-based research or to this community. It was first published in the United States. The numbers are as given to rules in the book: there are 1406.


266  _Predicting behaviour_ The best predictor of future behaviour is past
behaviour.

442  _Offending people_ The people who offend others most easily are often
the most easily offended themselves.

157  _Measuring things_ The first joint of your thumb measures about 1 inch,
your foot measures about 1 foot, and your pace measures about 1 yard.

415  _The library rule of 20/80_ Twenty per cent of a library's patrons
account for 80 per cent of the library's use. Twenty per cent of the books in a
library account for 80 per cent of the library's use. (Also applies to
contributors and funds, products and profits ... cf. 492, 493.)

1298  _Looking for engineering correlations_ If you are trying to describe a
phenomenon rigorously, correlate aggregate variables in such a way that the
units cancel out. For example, don't study the effect of changing pipe diameter,
which has units of distance. Study changes of pipe diameter divided by pipe
length, which has units of distance divided by distance. The result is
dimensionless. These correlations are more resilient to changes in materials and
scale.

31  _Measuring snow_ One inch of rain would make ten inches of snow.

61  _Determining the age of a spruce tree_ You can determine the approximate  age
of a spruce tree by counting the layers of limbs on its trunk. A tree that has
ten layers of limbs is roughly ten years old.

626  _Cleaning a park_ The number of people and the amount of litter decrease with
the cube of the vertical distance and the square of the horizontal distance to
the trailhead.

880  _Protecting your data_ In the computer world, make a copy of anything
that's important. If it's really important, make two copies.

1209  _Looking over a computer manual_ If a manual's table of contents lists
names of programs or components instead of tasks, the manual isn't user
friendly.

350  _Picking a programmer_ Never hire a computer programmer who knows only
one programming language.

373  _Writing computer software_ A software writer can be expected to
generate about ten lines of debugged, high-order language a day.

1253  _Writing a computer program 1_ When writing a long computer program,
figure out the data storage first, the input and output next, and only then
write the parts of the program that actually do the work.

1254  _Writing a computer program 2_ Write the documentation for a program
before you write the program itself. In other words, figure out how you are
going to explain the program to the user, then write the program to fit the
documentation.

1255  _Writing a computer program 3_ To write a good program, write and debug
the entire program, get it documented and working perfectly, then start over
again from scratch based on what you learned the first time through. This
process can be repeated as many as four times and still be cost-effective, but
you should always do it at least once.

1256  _Writing a computer program 4_ In most computer programs, 10 per cent
of the program accounts for 90 per cent of the processing time. Finding and
re-writing this part of the program so that it runs fast is always
cost-effective.

1257  _Writing a computer program 5_ No good computer program can be written
by more than ten people. The best programs are written by one or two people.

1338  _Illustrating your data_ If your data include fewer than twenty pieces
of information, a graphic presentation is unnecessary.

**Anonymous: I.J. Good?**

This paper appeared in a mostly serious, partly facetious collection. The Editor, I.J. Good, was a highly productive and moderately quirky Bayesian, and it's possible that Good himself contributed to this list. 

Anon. 1962. Bloggins's working rules. In Good, I.J. (Ed.) _The
Scientist Speculates: An Anthology of Partly-Baked Ideas._ London:
Heinemann, 212--213. 

[p.212] 

1. Murphy's edict -- if something can go wrong it will. 

2. If a problem has less than three variables it is not a problem. If it
has more than eight, you cannot solve it. 

3. Parkinson's Laws state:

(i) Work expands to fill the time available for its completion,
especially when it is interesting. 

(ii) A man starts to lose his grip five years before retirement age,
whatever this may be. 

4. Hartree's Law states that whatever the state of a project, the time a
project-leader will estimate for completion is constant. A task always
takes twice as long as one might reasonably expect. 

5. All reports require three drafts. 

6. The 20:80 rules: 20 per cent. of the people drink 80 per cent. of
the beer. It is prudent to assume the same concentration of effort
elsewhere, and Holt's Rule to forecast time series states: 

New forecast
$=$ 0.2 (Last result) + 0.8 (Last forecast). 

7. When there are unknown scale factors, assume a 0.70 power law. 

8. Numbers in real life usually have a 25 per cent. coefficient of
variation and rarely less than 10 per cent. Data usually have at least 1
percent. of gross errors. This applies to people too. 

[p.213] 

9. The best experts resist innovation, for they wish to remain experts,
and they are right only three-quarters of the time. 

10. The variance of cumulative chance events is practically infinite. 

11. Edie's Limit. Pooled Services may be more effective in theory, but
they are soon degraded by difficulties of switching and scanning. Edie
found 4--6 channels the most efficient group size for toll booths. The
same number must often apply elsewhere. 

12. Anyone more than two years younger than oneself is inexperienced. Anyone more than five years older is past his best. 

13. Any useful classification has 3--6 sub-categories, but a thirty-fold division provides a fine monument to hard work. 

14. Really top brass takes one year to make up its mind in matters in which you are interested. 

15. Do not ask questions on which people have no real opinions, or which they will not answer truthfully. Socratic dialogue is more potent than any arithmetic. 

16. There are never less than three conflicting criteria of merit. At best, operational research is nearly right. 

17. Life is 

(i) Discrete. 

(ii) Non-linear. 

(iii) Non-zero sum. 

(iv) Non-commutative, and positively irreversible. 

(v) Multiplicative rather than additive; the log normal distribution is more normal than the normal. 

18. One nearly always has prior knowledge, but optimisation? It is a delusion. Probabilities are always conditional -- very conditional. 

19. There are no decision rules to choose decision rules. 

20. The only practical problem is what to do next. 

21. The art of being correct lies in making the weakest possible statements. 

[ends] 

Notes by NJC: 

Edie, Leslie C. 1954. Traffic delays at toll booths. _Journal of the
Operations Research Society of America_ 2(2): 107--138.

Leslie C. Edie (1914--1990) was an early pioneer in operations research and transportation science. 

Douglas Rayner Hartree (1897--1958) was a mathematician and physicist who contributed to numerical analysis and its application to atomic physics and to the development of computing machinery. 

Charles C. Holt (1921--2010) is known for modelling and forecasting methods using exponential smoothing. 

Cyril Northcote Parkinson (1909--1993) was a naval historian and author of many books, most famously advancing Parkinson's Law.