# Testing

• ### Fermi on Hypotheses

There are two possible outcomes: If the result confirms the hypothesis, then you've made a measurement. If the result is contrary to the hypothesis, then you've made a discovery.

Enrico Fermi (1901 - 1954)

• ### Pirsig on Hypotheses

For every fact there is an infinity of hypotheses.

Robert M. Pirsig (1928 - )

• ### Armstrong on Hypotheses

Hypotheses, like professors, when they are seen not to work any longer in the laboratory, should disappear.

Henry Edward Armstrong (1848 - 1937)

• ### Ramseyer on significance

Old statisticians never die - they just become nonsignificant.

Gary C. Ramseyer (1934 - 2012)

• ### Huxley on Hypotheses

The great tragedy of Science - the slaying of a beautiful hypothesis by an ugly fact.

Thomas H. Huxley (1825 - 1895)

• ### Lorenz on Hypotheses

It is a good morning exercise for a research scientist to discard a pet hypothesis every day before breakfast. It keeps him young.

• ### Durand on Degrees of Freedom

The number of degrees of freedom is usually self-evident - except for the analysis of data that have not appeared in a textbook.

David Durand (1912 - 1996).

• ### The P-value Polka

May be sung to the tune of "Roll out the Barrel" (Lew Brown, Wladimir A. Timm, Vasek Zeman and Jaromir Vejvoda)

What's a p-value?
Test a hypothesis and see.
What's a p-value?
It is the probability,
That a new test statistic,
Would be at least as extreme as the old,
Given Ho is true.
That is what I'm told!

• ### Use a t

may sing to tune of "Let it Be" (Paul McCartney/Beatles)

When I find myself with normal data,
William Gosset comes to me
Speaking words of wisdom, Use a t.

If my NP plot is linear
but sigma isn't known to me
This is not a problem, Use a t.

Use a t, use a t, use a t, use a t
Student knows the answer: Use a t.

And when the broken hearted students
in a stats class can't agree
You can show the answer: Use a t.

Some want to use a Z test,
and a chi-square is a mystery
The truth is very simple: Use a t

Use a t, use a t, use a t, use a t
Student knows the answer: Use a t.

And when your thoughts are cloudy,
RA Fisher may not hear your plea
But Gosset will deliver, with a t.

He knows you are trying
and he wants to set your mind at ease
Don't think twice about it, use a t.

Use a t, use a t, use a t, use a t
Student knows the answer: Use a t.

• ### Hypothesis Testing is Fun!

may sing to tune of "Mr. Bojangles" (Jerry Jeff Walker)

Well, I didn't think I'd ever like statistics,
and I don't know why.
so I gave it a try.
And I've changed my mind, yes I've changed my mind,
'cause it's clear to me now,
Hypothesis testing, hypothesis testing, hypothesis testing is fun!

Oh, you state your null hypothesis and don't forget,
It may be directional that means it has one tail,
but usually two.
You decide on alpha, oh, don't forget alpha,
to control errors Type I and II.
Hypothesis testing, hypothesis testing, hypothesis testing is fun!

Then compute your z or t or F or chi-square,
and compare it to the table.
To decide the fate of your own null hypothesis,
you reject it if you're able.
If you're lucky you reject it, don't try to accept it,
it's not logical to do.
Hypothesis testing, hypothesis testing, hypothesis testing is fun!

So statistics really can be quite enjoyable,
if you study all along.
And I want to world to know about the joy I've found,
so I wrote this song.
And I hope you'll sing it, yes hope you'll sing it,
in a voice clear and strong.
Hypothesis testing, hypothesis testing, hypothesis testing is fun!