Confidence Interval - an Epic Poem

by Daan van Schalkwijk

A squire teaches the High King statistics to overcome a crisis of confidence, at risk to his own life.
Just when the High King is at loss in whom to confide, a squire offers to solve his problems by teaching him about confidence intervals; but when the King's senior sage protests, he must learn to see what statistics can and cannot do, or the sage will have him on the gallows.

Student Quotes

"The poem is just great. What a good initiative to describe something which students usually find not so interesting in a fun way."
Jovana Karanovic, student at Amsterdam University College, at her request this poem was written.

"I'm glad I returned to read the poem more carefully. I like how it speaks to the limits of quantitative reasoning at its conclusion."
Megan Myles, exchange student at Amsterdam University College from Quest University, Canada.

"I believe the poem is great, and it is quite impressive the fact that it took you so little to write it! The language is really convincing, and I love the last paragraph, it is really a nice conclusion!"
Kalliopi Theocharidou, student at AUC.

"For the High King the courageous squire turns on the lights,
For students, statistics is elevated to epic heights"
Job Zegers, student at AUC.

What's in it for... students of statistics?

A fun way of seeing whether you have understood the concept of confidence intervals, its advantages and limitations.

What's in it for... Policy makers and managers?

A timely reflection on the use of quantitative data in policy and management.

What's in it for... Everyone?

An epic poem with a short enjoyable adventure that will take you back to heraldic times, and help you polish your command of the English language!

Copyright 2012 Daan van Schalkwijk
Cover design by Richard Prins and Daan van Schalkwijk

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Cover image source attribution (Both images were modified)
Crown image - released under a Creative Commons - Attribution ShareAlike 2.0 license - Image by Sodacan on
Smiling boy picture - released under a Creative Commons - Attribution NonCommercial ShareAlike 2.0 license - Picture by Espen Faugstad (noxstar) on

Some seldom used English terms

Bell curve: Normal or Gaussian distribution
Candid: frank and honest
Canny: shrewd and careful
Contention:  assertion made in an argument
Expound: explain or make something clear by giving details
Gauge: measure; make a judgment about
May chance be: may happen to be
Ordain: order or command
Sage: very wise man
Stout: determined, brave, and resolute
Squire: Young man who was a knight's attendant until he himself became a knight.
Valiant: brave or determined
Mostly from 'Oxford Advanced Learner's Dictionary'

Confidence Interval - an Epic Poem

For my Basic Research Methods and Statistics I students, at Amsterdam University College.

'My dearest people, oh my people'
The High King sighed in his high hall,
'Oh, how my heart desires to know you,
But could I count you? Not at all!'
'So I have sent for sage and wizard,
To tell me how to serve you best.
But do my confidence they merit?
Oh my poor heart won't give me rest.'
'Oh Sire, Sire' cried a squire,
-Was sternly told to keep his still-,
But he went on, 'Thy need, so dire,
I can alleviate; I will!'
'Then let him speak' declared the High King,
A kindly smile shone in his eyes,
'For the advice this lad will offer,
May chance be canny, if not wise.'
'With your permission, Royal Highness'
Up stepped the squire, with rev'rend bow,
'If it be confidence thy seeking,
I can provide it, I know how.'
'A valiant promise, master squire,
Then let us have it, we're all ears.'
A hidden grin ran through the courtiers,
But our stout squire knew no fears.

'Then well, for starters, take a sample,
Take it as random as one can,
From all the people in thy country,
May they be woman, child, or man.'
'Then from the sample, we must measure,
Whichever size thou longst to know.
It could be tallness, wideness, deepness,
Strength of arm or width of bow.
'And now the trick, your Royal Highness,
That thee will grant thy dream so dear:
It from the averaged sample measure,
Will know your people without fear.'
'I do object, your Royal Highness'
Cried out the kingdom's senior sage,
'What madness does this scoundrel tell us,
So hot of blood and young of age?'
'Have patience, patience, wise advisor,
Let now the young man prove his claim.'
'Well this is certainly unheard of,'
The sage then muttered, 'on my fame.'
'Your Royal Highness,' said the squire,
'Let me then liberally expound,
Confiding in your royal mercy,
The one solution I have found. . .

'The central claim of my contention:
If now large samples one would make,
Then many means would form a bell curve,
Your people's mean the top would take.
'If one now has a single sample,
And wants with confidence to say,
Oh, where the people's mean is lying:
It is surprising, but one may.
'Say one wants confidence at level,
Of even ninety-five percent,
Then one finds all thy people's values,
One may, from sample's worth, defend.
The high- and lowest of these values,
Give us a bell-curve that lies so:
The sample mean does mark the outskirts,
With two-and-half percent to go.
'And thus thou hast a range of values,
That people's value doth contain,
In ninety-five percent of times when
Thou this procedure wouldst ordain.'
'Onto the gallows' cried the sage then,
The anger flushing in his face,
'What blackest magic he expoundeth,
He rings a bell and lifts a haze.

'Sire even if you found it candid,'
Went on the sage in breathless tone,
'For all his valiant youthful promise,
Thy getst thy people's mean alone.'
'Beloved High King' cried the squire,
His features raging with alarm.
But now the High King would have silence:
He raised majestically his arm.
'My sage, thy words have proved thy wisdom
When even angered, all the same,
But then for thy request to hang him:
Well, oh my good Lord, oh for shame!
'For indeed the boy proved canny,
Though perchance he be not wise.
And though there be some boastful promise,
There's loyal service in his eyes.'
'And it's just this, young master squire,
That all your measures do not show:
For I would gauge my people's spirit,
Their faithful loyalty to know.
'And therefore, for your boastful promise,
You from your squire state I'll fling.
For your intelligence and daring,
You're now the student of the King.

'Full well I recognise the promise,
Held by the method that you show.
But it requires a humble spirit,
Its strengths and weaknesses to know.
'So study numbers, nice and certain,
Of people's money, strength, and arts.
But let all hearers now remember:
The King cares more for people's hearts!'
Daan van Schalkwijk,
11th of November 2012

Questions to aid reflection

These questions can be used for private reflection, but are perhaps most effective as discussion questions in a seminar or in an in-class discussion.

For statistics students

Could you reproduce in your own words the squire's explanation on the construction and interpretation of confidence intervals? Do you follow what he says?
The King remarks that the sage has spoken wisely, except for his condemnation of the squire. Do you agree with the sage? Is it true that a confidence interval only gives information about the population's mean, or is there more to it? What valid point does the sage's position imply?
The King's final words point towards the strengths and weaknesses of statistics. How would you formulate the strengths of statistical theory, and how would you formulate its limits?

For policy makers and managers

Policy and management are nowadays mostly evaluated on to what extent certain quantitative targets have been reached. In contrast, the poem starts with the King's desire to get to know his people. Is the King's desire therefore archaic? How do you see the relationship between the 'hard' targets and the 'soft' people management in your daily practice?
The sage in this tale is afraid of being ousted by the force of the squire's quantative methods. What is the role of listening to the advice of experienced people versus quantative indicators in policy or management decision making in your daily practice? Are you happy with the current balance?
The king states that he 'cares more for people's hearts' and evidently values their faithfulness to his person highly. Is your personal relationship with the people you lead or manage of importance to you? Is it something you give enough attention to?

The Harambee Project

This project is part of a crowdfunding drive for the Harambee USA NGO. The following description is taken from their website (

"What Harambee USA does is more than an act of charity for a people in need. It is an act of belief in a people who are passionate about advancing their community and an act of hope in a young and vibrant continent." Kevin Kambo, Strathmore University graduate, Kenya

Founded in 2007, Harambee USA Foundation is a US non-profit 501(c) 3 organization designed to promote international solidarity and cooperation with sub-Saharan African countries. We are a National Associate of Harambee Africa International, an Italy-based non-profit at the head of the Harambee network. Our two-fold mission is:
In sub-Saharan Africa: To support sustainable educational and developmental initiatives that help Africans help themselves.
In the United States: To promote awareness-building programs for all ages to transmit the richness and complexity of African culture.

Harambee USA Foundation does not make capital grants. In sub-Saharan Africa we focus mainly on short-term or technical assistance grants for programs with explicit objectives and pre-determined costs. We support education at all levels and projects with at least partial local funding. Our operational structure guarantees proven effectiveness and financial accountability.
To preserve its original integrity and limit overhead costs, Harambee USA Foundation is 100% volunteer-staffed. Our team is comprised of enthusiastic professionals from diverse nationalities and educational backgrounds, fully dedicated to the Foundation's mission and vision for the benefit of Africa.
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Why does a Dutch teacher support an NGO in the USA? Because this book is published at Smashwords, an American publisher. In this way the proceeds from the book sale can go directly to the NGO, without much hassle. (For the book, see
For Dutch citizens who would like to make a tax-deductible gift, they can transfer to account nr 6494736, t.n.v. Stichting De Oude Gracht, Amsterdam, o.v.v. "Harambee". These gifts will be transferred directly to Harambee International, the overarching worldwide NGO that supports the same projects as Harambee USA.

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Resources for Teachers / Seminars

Hand-out versions of the poem are available in pdf format.
For statistics students: A4 (, US letter (
For management seminars: A4 (, US letter (

About the Author

Daan van Schalkwijk teaches Basic Research Methods and Statistics I, as well as a course on Systems Biology, at Amsterdam University College. He is also the director of Leidenhoven College, a small-scale collegiate hall of residence in Amsterdam. Furthermore he works as a scientist-innovator at the TNO research institute. He regularly writes poetry for Omega magazine.
I wrote this poem because I want to inspire my students. Statistics is now an ordinary part of everyday life, but that was not always so, as the strangeness of statistics at a medieval royal court helps you realize. That makes us grateful to have such a great tool available. At the same time, the King reminds us of aspects of our humanity that may have become undervalued because of our insistence on the importance of quantitative data. So while the King may learn from us, we may also learn from him...
Through the Harambee fundraising drive I both hope that the poem may inspire people beyond my classroom, and that together we may support education in Africa. It would be great to give Harambee a well-deserved royal gift!

Where to find me online
My blog: (English) (Dutch)

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