Thread by @TimHarford

HAPPY WORLD STATISTICS DAY EVERYONE!

World Statistics Day only comes every five years - like the Olympics - so it's time to express a little mindful gratitude for all the statisticians and other wonderful nerds out there helping us to understand the world.

Since I literally wrote the book on the topic, I’d like to mark the day by sharing my TEN RULES FOR THINKING DIFFERENTLY ABOUT NUMBERS. Each of us could be thinking more clearly about the world if we got ourselves right with the numbers. timharford.com/books/worldadd…

So, Rule One: SEARCH YOUR FEELINGS.
What we believe, or refuse to believe, is strongly influenced by our emotional reaction. A lot of the statistical claims we see aren’t just data: they are weapons in an argument. Social media thrives on emotion. So do media headlines.

I don’t think we can or should ignore our emotions or values. But we should get into the habit of noticing them. If the reaction to a claim is a knee-jerk, “this proves I was right!” or “Fake news.”, we need to count to three and start thinking more clearly.

Rule Two: PONDER YOUR PERSONAL EXPERIENCE. We get information from graphs and spreadsheets. We also get information from the rich and vivid experiences all around us. To adapt Kahneman, there are “statistics, fast and slow”.

Often our personal experience conflicts with the data. Sometimes the data are misleading. Sometimes it’s our own experience that is skewed in some way. One thing I learned from the great @HansRosling was that the best insights come when we are able to combine the two.

Rule Three: AVOID PREMATURE ENUMERATION. One of the perils of being numerate is the temptation to start chopping up numbers – computing ratios, rates of increase, means and variances – before we understand what they refer to.

Arguably the financial crisis of 2007-08 was caused, in part, by very sophisticated mathematical analysis of measures of risk which were poorly understood. Start by understanding what the numbers refer to, eh?

(Sorry for the break. Just had to pop onto @BBCr4today to beat the drum for WORLD STATISTICS DAY.)

Rule Four: STEP BACK AND ENJOY THE VIEW.
Rather than focusing on the latest data point, get some context. What has happened to this data series over the past year? Past decade? What is happening elsewhere? Are there any comparisions which help make sense of the number?

For example - here, @standupmaths and I ask how many dinosaurs to the bus? (And other vital questions.)

Rule Five: GET THE BACK STORY.
Every number is in front of your eyes for a reason – often because it is particularly surprising. It may be surprising because it is not representative of a wider trend. It may be surprising because it is flat-out wrong.

The “replication crisis” in psychology came about as scholars realised that peer-reviewed work was subject to a powerful “interestingness” filter – good-but-dull work was buried, while flukes were published. But that same powerful filter, publication bias, is everywhere.

Rule Six: ASK WHO IS MISSING. You’ve all read @CCriadoPerez 's “Invisible Women” (I hope) – about how the data we gather often miss the needs of women, or fail to disaggregate so that we can ask questions about the different experiences of women and men. amzn.to/31nTf1C

And once you start thinking like that, you see data gaps everywhere – from the shy Trump voters who pollsters missed at the last election, to grand big-data based claims that only measure those of us with smart-phones.

Rule Seven: DEMAND TRANSPARENCY WHEN THE COMPUTER SAYS ‘NO’

Algorithms are providing some amazing insights – but very often they are commercially confidential.

Senior managers & politicians swallow tall tales about the power of the algorithm (eg “this algorithm will give everyone the perfect A-Level grade”).
But those grand claims are often unproven. We should demand better evidence and independent scrutiny.

In “How To Make The World Add Up” I write about the history of alchemy vs science. Same methods, same people, different results: largely because science involved collaboration, open experimentation and scrutiny. Alchemy was all done in secret.

Rule Eight: DON’T TAKE STATISTICAL BEDROCK FOR GRANTED
And this is the real message of World Statistics Day. All around us, statisticians and other hero-geeks are painstakingly gathering and analysing the numbers we need to understand what is happening all around us.

The pandemic provides a vivid example: how does the virus spread? Where is it now? How dangerous is it? Who is most at risk? What sort of settings or behaviours increase the risk? What treatments are safe and effective?
Such questions can’t be answered with statistics.

But we’re trying to answer other questions – about crime, the economy, demographics, health, the environment and more – all the time. The statistics are quietly and carefully assembled and we take them for granted.

We just assume they will always be there when we need them. We notice only when something goes wrong. That is a shame. So let us celebrate the wonderful folks who help us see the invisible all around us.

Rule Nine: REMEMBER THAT MISINFORMATION CAN BE BEAUTIFUL TOO
The hero of my chapter nine is Florence Nightingale – someone who really understood the power of data visualisations to win an argument.

But there is a risk in data-visualisations. Alberto Cairo points out that our visual sense is so potent we use phrases such as “I see” as a synonym for “I understand”. Very often, however, the understanding is illusory – we’ve been fooled by beauty. amzn.to/2IMmXqC

All the other rules apply, with double force, when looking at a picture of data.

Rule Ten: KEEP AN OPEN MIND
Easy to say, isn’t it? But what I mean here is a willingness to keep examining the data and being able to admit to yourself and others that you have changed your mind.

Irving Fisher, one of the tragic heroes of Chapter Ten, was a genius – but failed to change his mind when it mattered. He lost everything.
A rival, not without sympathy, said that Fisher’s undoing had come because “he thinks the world is ruled by figures instead of feelings”.

I hope this thread has persuaded you that in fact, the world is ruled by both.

I should add: all too often, statisticians are prosecuted, persecuted, threatened, or in extreme cases executed - all for speaking truth to power.
Some of these tales are in "How To Make The World Add Up".
A sobering piece in @signmagazine here:

https://twitter.com/i/status/1318444207405748225

BONUS! FREE EXTRA GOLDEN RULE!
The Golden Rule is...

Be Curious.

The world is a fascinating place, but many of the things that make it fascinating are people too numerous ever to meet, patterns to subtle to detect unaided, or other truths that only statistics can reveal...

...so have a little confidence in your ability to make sense of the numbers, and show some curiosity. Ask what's going on in the world - and how numbers can help to illuminate it.

Happy #WorldStatisticsDay everyone!

Oh, I notice that (perhaps in celebration of #WorldStatisticsDay ), the excellent "Bad Science" by @bengoldacre is selling for 99p on Kindle.
amzn.to/3dJLNmn

Beats paying £75 for the Bad Science hardback, I must say..