Every day, we get an update on Covid-19 cases and deaths. Or we hear about police having confiscated this many items of contraband. Without context, such numbers are meaningless at best, and may be intended to deceive.

One of my biggest gripes with media reporting is the naïve treatment of numbers. It’s as if journalists can’t do basic arithmetic, can’t visualise numbers in their head, or couldn’t be bothered trying to think about what numbers mean.

Whenever you come across a big number, ask yourself, ‘Is that a lot, or not very much at all?’

There are many ways to reach an answer, but countless newspaper articles don’t give you the information to contextualise the numbers they trumpet in their headlines. Often, the numbers serve the interests not of the reader, but of those whose press releases the media uncritically parrots.

Daily Covid-19 numbers

Every day, we get a Covid-19 update. For most, it will come in the form of a newspaper headline, such as this: ‘South Africa records 144 new Covid-19-related fatalities as death toll climbs to 12 987’.

The article itself is not much more informative. It adds that there are now 607 045 confirmed cases, and 504 127 recoveries, for a recovery rate of 83%. It then breaks down the case numbers by province.

All this data is totally useless. What readers want to know is how bad things really are, and whether things are getting better or worse. None of these numbers, in isolation, answer any of these questions.

Alex Welte, writing for GroundUp, does a great job explaining why the recovery rate does not mean what you might think it means, and is a ‘lousy measure of how we’re doing’.

As the epidemic rolls on, a greater number of all the cases ever recorded get resolved, so it stands to reason that the recovery rate will gradually increase, the longer the epidemic lasts.

He also notes that the underlying numbers are questionable. We don’t really know how many Covid-19 deaths there have been, as some number undoubtedly happened in circumstances where they could not be counted.

We also aren’t sure about the infection numbers. We don’t know how many people with no or few symptoms present themselves for testing. Even among people who do get tested, we have the problem that perhaps 30% of results could be false positives, and many more could be false negatives, especially if the tests are conducted in the early days of the infection. Even at the optimum of eight days after infection, 20% of tests return false negatives.

If we’re not sure about the real number of cases, and the real number of deaths, we can’t possibly rely on a composite statistic such as the case-fatality ratio (CFR) to give us a better idea of where we’re at. If you divide garbage by garbage, you get worse garbage.

Where are the charts?

What we should do, is look at trends. Are things getting worse, or are they getting better?

Newspapers should be publishing charts, not daily numbers. Government should be publishing charts, not daily numbers. We know that the country is over the peak, but sadly, charts that indicate trends in infections or deaths are few and far between (or behind paywalls so only a handful of rich people get a look at them).

Even the charts that the National Institute for Communicable Diseases (NICD) publishes are not particularly useful. They show cumulative cases and deaths, which suggests a flattening of the curve, but not daily cases and deaths, which would confirm that suggestion.

The NICD’s age distribution chart is meaningless because it is not normalised. We know we have few old people, so we shouldn’t be surprised there are few cases among old people, and that the curve skews much younger than elsewhere in the world. The question is how the chart would look if you divided cases or deaths in an age category by population in that age category.

Much is made of the fact that South Africa ranks fifth in the world in terms of the number of cases, but we’re only 21st in terms of number of cases per million population. We rank 13th in terms of total deaths, but only 29th in terms of deaths per million population.

Why aren’t numbers reported per capita? It is of no use to know that we have more cases or deaths than some small country with five million people. To make a comparison, we must have per capita numbers.

Why is it that everyone knows the ‘fifth in the world’ factoid, but few know that per capita, our death rate is not at all extraordinary? Why does everyone know about 13 000 Covid-19 deaths, but nobody knows that influenza kills 11 000 every year, and this year, there appears to be no influenza at all?

Without context, daily Covid-19 numbers are meaningless. They’re a waste of valuable screen time that could more profitably be spent arguing with bigots on Facebook.

Busting smugglers

Or take this article: ‘SARS has confiscated illegal cigarettes worth R77m during lockdown, says Mboweni’.

Mboweni placed this number into some sort of context by saying this compares to R15 million during the same period last year.

Now, is R77 million a lot? Does quintupling the haul of contraband mean the taxman has done a good job cracking down on the black market?

Let’s leave aside that there is no way to tell the value of a given haul of cigarettes when there is no legal market. Were the confiscated cigarettes valued at pre-lockdown prices, or at black market prices? Black market prices varied widely by location and over time. (For the same reason, never trust a value that police place on a drug bust. They have no clue what the true street value of a big haul is.)

There is no good estimate of the total size of the black market in cigarettes, but we can piece together some estimates to put that R77 million into context.

The legal South African tobacco market, in 2017, was valued at $2,7 billion, or about R45,7 billion at today’s exchange rate. All cigarettes were illicit during the lockdown, and the ban lasted about four months. About 90% of the country’s 11 million smokers continued to smoke during lockdown. Illicit cigarette prices were on average 250% higher than pre-lockdown prices.

That leaves us with a total estimated black market size of as much as R34 billion, or, if we assume smokers cut down by 50% to compensate for higher black market prices, some R17 billion.

That means R77 million represents less than half a percent of the total illicit cigarette market during lockdown. Those are pretty decent odds for black market dealers.

How about last year’s number, then? Well, before the lockdown, the illegal trade accounted for between a third and half of all cigarettes sold. Using the conservative estimate, that means SARS confiscated about 0.3% worth of the illicit market.

So although SARS was marginally better at finding illegal cigarettes when all cigarettes were illegal, it was not particularly effective in curbing the illegal tobacco trade during lockdown.

A better headline would have read: Mboweni admits SARS failed to seize more than 99.5% of illegal cigarettes during lockdown.

Numbers need context

There are countless examples of contextless numbers that are presented as somehow having meaning.

Financial amounts involved in corruption cases. Kilograms of CO2 emitted by this or that activity. Acres or hectares of land affected by a fire. Number of views on YouTube. Stock prices. Project spending.

If a news article says that a company is building a R100 million facility, is that a lot? Or are they getting value for money? If it says Eskom is building a R150 billion power station, is that much? Should they cost a lot less?

Unless you’re an expert in the field, you simply can’t know. Numbers in news reports would be far more informative with added context. Compare them to the past to show trends. Compare them to similar events to gauge whether they’re high or low. Compare them to totals to get a sense of scale. Use averages. Normalise data.

Without context, numbers can convey a lot of things – irrational fear, undeserved praise, misguided outrage – but they cannot convey useful, actionable information. Often, those who produce those numbers are counting on that.

[Picture: Gerd Altmann from Pixabay]

The views of the writer are not necessarily the views of the Daily Friend or the IRR

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23 COMMENTS

  1. You are so correct. What I cannot understand is why the government continued to ignore the advice of the grouping of professionals called PANDA. When they released their initial report, I can understand the government’s reticence, but with the 20/20 vision of hindsight showing that PANDA was right and the NICD was wrong, why not start listening to actuaries and economists? I have found they are generally pretty good with predictions.

  2. Serious question, what makes a real & “trustworthy” Journalist? Also with numbers, Farm murders declining, well there are no more farmers to kill, ditto Rhinoceroses.

    • A real and trustworthy journalist? You have to pick one, you can’t have both. A real journalist is one whose writings fit the narrative, even though the facts are wrong. A trustworthy journalist would have an incredibly tough time finding employment, in the post-truth era of fourth estate vanguardism.

  3. Good article. I have no trust in the (any) Government that they want to have “the best”. Their actions are filled with hidden agenda’s. Not for us, for “them”.

  4. South Africa is dealing with two forms of garbage; government and media and nearly everything the two say.
    The Covid-19 statistics are completely hogwash. 95 % of people remain obedient, submissive, ignorant and stupid. Masks don’t defend against any virus and yet the majority act is if their lives depend on it while continuing to brainwash their children. Forcing children to wear masks is child abuse.
    When farmers and white people are tortured, raped and murdered the media refuse to broadcast these atrocities but when something happens to a black person then the world is informed.
    What the f… is going on here? This is madness!

  5. Numbers, one of the oldest games in town, understood by so few but quoted by all. A most powerful tool useful for manipulating fools and kings. In a enlightened new world one can imagine a complete new way of teaching mathematics/numbers in schools and universities.

  6. I have long ago stopped paying attention to figures published by mainstream media, precisely because of the lack of context or comparable figures.

    I had first hand experience, for example, about the uselessness of the Covid-19 tests.

    My son’s girlfriend caught a cold/flu in the 2nd week if July. She had to go to one of the public hospitals on 23rd July. As it goes, the questionnaire asks if you are short of breath, have a cough, has body pains or lost your sense of taste or smell or have experienced the above in the last week.

    She answered yes, although the shortness of breath was caused by anxiety, so was the coughing. The loss of smell due to her blocked nose from the cold and body pains because she had started a new exercise plan.

    They took the swab, sent her home and phoned her 4 days later to tell her that she tested positive for Covid-19.

    By then the cold had run its full course and her body had adjusted to the exercises, even though she still had some anxiety.

    She never had Covid-19, so her test was a false positive.

    Keep in mind what the Covid-19 test looks for – the presence of Corona virus DNA in your throat. Also remember that the viruses causing the common cold and the flu are all Corina viruses.

    If 11 000 people died of flu this year and they all tested positive for Covid-19 because of the above fact, that basically means that probably only 2 000 people possibly died due to Covid-19.

    See how easily the figures can be manipulated to portray a totally different picture?

  7. What about percentage changes? Headlines about a 50% increase when the numbers say moved from 30 to 45. 15 more doesn’t sound too bad but 50% sounds alarming.
    Context/real world so often ignored.

  8. Well done Ivo vegter. The numbers are there to drive an agenda.
    Many are unaware that the tests that are used to support the number are in fact farce of the WHO. They have just been dealt a major blow of course unreported by our untrustworthy MSM.
    It has been a long time coming. Off-Guardian called the tests “COVID19 PCR Tests are Scientifically Meaningless” back in June.
    Here is the link- https://principia-scientific.com/farce-un-pcr-test-reads-any-human-dna-as-covid19-positive/

  9. Very good article, Mr. Vegter. I give it two thumbs up biiig time… As the old saying goes, there are lies, damned lies and then there are statistics. Whenever I hear a government official say something, I think of it as a reenactment of the scene from Animal Farm where the pigs sit around a table, make speeches, quote meaningless statistics, then dive into their sumptuous meal. As for the media, when they’re not parroting the official line or unquestioningly copying articles from AP and AFP which contain errors, they’re mostly too dumb to know the difference between “grizzly” and “grisly”. I’m not exaggerating, just look at this… https://www.heraldlive.co.za/news/2020-08-22-burnt-decapitated-and-fed-to-pigs-grizzly-trail-of-murders-grips-east-rand/

    I’ve been watching the media for quite a while now and have noted many instances where I strongly suspect collusion between journalists and government figures. As The Herald article shows, and it’s only one example of many, the quality of journalism and editorial quality control has dropped alarmingly, but beyond a few people mentioning this just before some journalists are retrenched or a couple are found to have published bs stories (think the SARS Rogue Unit and Cato Manor death squad cases, but there are more), nothing really gets done. The Covid-19 stats are useless for the reasons stated above, along with the government’s desire to maintain the control it gained during lockdown through fear and media’s desire to make money out of click-bait, to say nothing of the unknown number of false test results, and impossibility to classify “Covid deaths” because medical personnel are scared to do proper autopsies and probably lack the resources to verify each case anyway. What’s worse, apparently only 22% of government hospitals even submitted statistics regularly, so we’re looking at a serious mess caused by a confluence of garbage data and lack of institutional capability that has translated into a feast for propagandists.

  10. Excellent perspective Ivo! This whole pandemic scare, was in my view, a storm in a teacup. Only thing is the teacup has been destroyed. Worldwide, millions of jobs have been lost. People will soon succumb to malnutrition, hunger and disease – especially in poorer countries. Whole industries have been wiped out. These factors will in turn cause soaring crime levels. The reaction to this pandemic has created fertile ground for dreaming up conspiracy theories. And the reason is clear: In 2018, the WHO showed figures of more than 3 million global deaths due to “lower respiratory infections”. Other studies have concluded that up to 650,000 people annually die form seasonal flu alone, while a further 200,000 may succumb due to complications associated with seasonal flu. An estimated 820,000 people have now reportedly died of Covid-19. But once again should be seen in context. Heart disease causes nearly 10 million deaths annually, while stroke is responsible for nearly 6 million deaths. Pandemics have been around since time immemorial. But how will the world react with the next virus scare? Will we be allowed to live “normal lives” only 25% of the time ahead, while 75% of the time will need to be spent watching economies crumble and our livelihoods destroyed?

  11. You are so correct. You should have added headline news (more than once) Cape Town approving a R5Million, not billion, project providing housing to eleviate the effect of Covid. I will not be surprised if it is all private money in its entirity and the developer has been struggeling for years to get the approval. In reality, it is the value of one apartment, not a house, in the CT waterfront.
    Who are they trying to impress?

  12. The first book by Isaac Asimov that I encountered in my teens, was a non-fiction collection of essays called “Only A Trillion”. Amongst other scientific essays, it was mostly about just how small a “big” number can be. I have been chary of “big” numbers (especially from news sources) ever since!

  13. I still follow the advice in Darryl Huff’s “How to lie with statistics”. His final chapter, headed “How to talk back to a statistic”, gives a list of five checkpoints:

    1. Who says so?
    2. How does he know?
    3. What’s missing?
    4. Did somebody change the subject?
    5. Does it all make sense?

    That list usually keeps the level of credibility in line.

  14. Thanks for your excellent article of the tyranny of context free statistics! I guess you’ve read Hans Rosling’s “Factfulness”, which amplifies your argument.

  15. Here is one (1) number that says a lot: I am reading exactly 1 (one) publication with some news and few opinions. Context is screaming in our face.

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