if I had just one shot to share an important idea💡here it is. No joke. Look 👀


👇 the coolest non-trivial example when a log Y-axis is required to represent ratios

going from 50 in ~1988 to 25 in ~2001 is as bad as going from 100 in 1970 to 50 in ~1988
Fascinating how the data story is changing – the seeming recent plateau is no longer there. And log *is* the *right* way to represent the nature of the data and tell the story.

The plots above are made by @CedScherer using @WWF data via @OurWorldInData
RATIOS appear whenever you divide something by something else of a similar class/nature. Ratios are dimensionless. The most common "hidden" case is time series standardisation when some year is taken for 100%, like 1970 in the example above
The thing is: the story (the shape of the line) will change depending on the arbitrary choice of the year taken as 100%. We divide all other years by this standard effectively creating *ratios*
I genuinely believe this is *the* most common #dataviz issue

It also often becomes a problem in statistical analysis – log transformation of the ratios are required before regression/correlation analysis is performed on the data
[side note]
It's even more important than the ones coming right after:
The realisation of this simple data visualization and analysis rule literally took me ages of slow mind walk: from odds ratios through other explicit ratios to the "hidden" ones like here. Even color bars in the plot legends should be log transformed if they colorcode ratios!
I lost track how many times I've pointed this out 😅


The idea to write a blog post on visualizing ratios correctly lives in my head and to-do list for well over a year now

Let me use this thread to legally bind myself to write it up soon 🔗

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More from @ikashnitsky

5 Apr
A fit for the #30DayChartChallenge Day 1 – my first attempt producing a treemap in #rstats

Let me tell you a bit about this big project of mine that I never really pitched here since it's in Russian language

A small thread on my Demographic Digest

🧵x12 unnumbered
I started Demographic Digest project in my second PhD year (or rather half a year after my modified PhD topic was set). Having struggled through the first feverish reading of the literature of the topic, I realised that I need to radically up the skill of skimming through papers.
Reading deeper and deeper into the specific domain of demographic literature, and not being 100% sure that this was even *my* topic, I also missed a lot a broader view of what was being discussed at the cutting edge of demographic debates.
Read 12 tweets
29 Mar
So. Today was marked w/ unimaginable punchdown attack of John Ioannidis at @GidMK published in a seemingly peer-reviewed academic paper

Reason: "this nasty phd student dared to expose me wrong"

Many wonder if those previously calling for civility would be as vocal now


For the context, @VPrasadMDMPH published this piece
calling for a more constructive academic discourse of the manifestly wrong IFR estimates by Ioannidis.

So sweet of him.
Let's see if @VPrasadMDMPH was equally mature, responsible, and wise when it was Ioannidis vigorously attacking (in a paper published in the journal where Ioannidis was editor in 2010—19) @GidMK for persistently and convincingly debunking his c19 research
Read 15 tweets
5 Mar
Demography 101


and (even more important)

❌ what it isn't ❌

Join in for the most topical demography primer

🧵 THREAD 1/x
Unlike many statistics and quantities of general use that we tend to see regularly, life expectancy is not observed directly. It's an output of a *mathematical model* called life table.

So, why can't we do without a model?

Consider a seemingly simple task: you want to know how long people live. What can be easier? Let's just see how many years lived those who died recently.

Why not?

Such a metric would be massively driven by population age structure

Read 30 tweets
1 Feb
How can one be satisfied with the "corrected" "finding" that literally claims that missing a couple of months of schooling is the most detrimental thing that can happen to a kid in the remaining life...

but (!) only if it's a US kid; if the kid is from Europe, all fine
Needless to say that @DAChristakis @drwilvancleve & @Zimmermanfred ignored many many other *critical* issues that we identified w/ @GidMK in their paper. See the full piece here osf.io/9yqxw

But of course "Christakis points out that the journal stands by his paper" 🤣
Just compare the two plots: before and after

What a beautiful CORRECTION @JAMANetworkOpen
Read 5 tweets
11 Jan
Two months since the publication, our critique w/ @GidMK (osf.io/9yqxw) caused the authors to revise the (remember, thoroughly peer-reviewed) paper and publish a correction


tl;dr: retraction is still the only way

how it started: how it's going: ImageImage
Now the paper's page at @JAMANetworkOpen mentions a correction, and 2 comments are published: ours (which is a very short summary of our critique, osf.io/9yqxw) and the response from the authors.


2/ Image
First, a side note: our comment was strictly limited to 3600 symbols (537 words); the authors' response comment is 1258 words


No wonder they keep insisting on the in-house discussion. So cute!

(and don't forget, Twitter is for trolls)

Read 21 tweets
20 Dec 20
Hi Michael,

I'm finally back with a properly comprehensive answer to your elaborated response – as promised earlier today I have a lot to say.

Welcome all to the new form of academic communication – an exchange of endless threads


But first, let me sincerely thank you for the open take of the debate – that's an honest and strong move 💪

I have to say, after the first, embarrassing tbh, reactions from the friend circle of the papers' authors I had very little hope for what's happening here.

Involvement of the authors in the open discussion of their results is a cornerstone thing in science. Mistakes are inevitable, and those who can't admit and fix them are hindering the scientific process.

We observe a painfully absurd case in parallel

Read 25 tweets

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