Hiahawatha designs an experiment



(шуточное стихотворение)

(Доугерти К. «Введение в эконометрику» с.22)

Hiahawatha designs an experiment

Hiawatha, mighty fighter

He could shoot ten arrows upwards

Shoot them with such strength and swiftness

That the last had left the bow string

Ere first to earth descended

This was commonly regarded

As a feet of skill and cunning.

 

One or two sarcastic spirits

Pointed out to him, however

That it might be much more useful

If he sometimes hit the target.

Why not shoot a little straighter

And employ a smaller sample?

 

Hiawatha, who at college

Majored in applied statistics[2]

Consequently felt entitled

To instruct his fellow men on

Any subject whatsoever,

Waxed exceedingly indignant

Talked about the law of error

Talked about truncated normals

Talked of loss of information

Talked about his lack of bias

Pointed out that in the long run

 

Independent observations                         

Even though they missed the target

Had an average point of impact

Very near the spot he aimed at

(With the possible exception

Of a set of measure zero).

 

This, they said was rather douptful.

Anyway, it didn’t matter

What resulted in the long run;

Either he must hit the target

Much more often than in present

Or himself would have to pay for

All the arrows that he wasted.

 

Hiawatha, in a temper,

Quoted parts of R.A.Fisher

Quoted Yates and quoted Finney

Quoted yards of Oscar Kempthorne

Quoted reams of Cox and Cochran

Practically in extenso

Trying to impress them

That what actually mattered

Was to estimate the error.

 

One or two of them admitted

Such a thing might have it uses

Still, they said, he might do better

If he shot a little straighter.

 

Hiawatha, to convince them,

Organized a shooting contest

Laid out in the proper manner

Of designs experimental

Recommended in the textbooks

(Mainly used for testing tea, but

Randomized his shooting order

In factorial arrangements

Used in theory of Galois

Fields of ideal polynomials

Got a nicely balanced layout

And successfully confounded

Second-order interactions.

 

All the other tribal marksmen

Ignorant, benighted creatures

Of experimental set-ups

Spent their time of preparation

Putting in a lot of practice

Merely shooting at a target.

 

Thus it happened in the contest

That their scores were most impressive

With the solitary exception

This (I hate to have to say it)

Was the score of Hiawatha

Who, as usual, shot with great strength and swiftness

Managing to be unbiased

Not, however, with his salvo

Managing to hit the target.

 

There, they said to Hiawatha

This is what we all expected.

 

Hiawatha, nothing daunted

Called for pen and called for paper

Did analyses of variance

Finally produced the figures

Showing beyond peradventure

Everybody else was biased

And the variance components

Did not differ from each other

Or from Hiawatha’s

(This last point, one should acknowledge

Might have been much more convincing

If he hadn’t been compelled to

Estimate his own component

From experimental plots in

Which the values all were missing

Still, they didn’t understand it

So they couldn’t raise objections

This is what so often happens

With analyses of variance).

 

All the same, his fellow tribesmen

Ignorant, benighted heathens

Took away his bow and arrows,

Said that though my Hiawatha

Was a brilliant statistician

He was useless as a bowman.

As for variance components

Several of more outspoken

Made primeval observations

Hurful of the finer feelings

Even of a statistician.

In a corner of the forest

Dwells alone my Hiawatha

Permanently cogitating

On the normal law of error

Wondering in idle moments

Whethering an increased precision

Might perhaps be rather better

Even at a risk of bias

If thereby one, now and then, could

Register upon the target.


Словарь эконометрических терминов

Adventure – событие 

analyses of variance – дисперсионный анализ

average point – среднее значение

bias – смещение

(to) compel to estimate – подчинить оценке, оценить

error – ошибка

(to) estimate – оценить

independent observation – независимое наблюдение

order – последовательность

(to) randomize – расположить в случайном порядке

sample – выборка

set of measure zero – бесконечно малая величина

statistics – статистика

truncated normals – усечение нормального распределения

value – значение

variance – дисперсия

 


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