Close Contacts & Lake Wobegon
Tags: Covid 19, Covid App, Cognitive Bias, Illusory Superiority

Over the weekend I have been thinking a lot about what happens next, as we come out of Level 5, and whether we might be able to live safely with the virus, rather than bounce in and out of further lockdowns. Let’s face it, we have not been doing so well to date, and the economic and social costs are mounting to say the least. Can we really afford yet another lockdown in the new year to pay for the inevitable excesses of Christmas?

But what is to be done? After all, so many of us feel that we simply cannot do anything more. For months we have been carefully observing social distancing guidelines, wearing masks when we are indoors, trying to avoid poorly ventilated spaces, and we have eliminated home visits from friends and family. And yet still we are back in lockdown. Sigh!

One of the best pieces of advice I have heard is that we should be halving our social contacts, because that will reduce the R number by 50%. That’s good advice because: (a) it is easy to understand and (b) if it happens, it will have a material effect on transmission rates. But is it really that straightforward? Anecdotally at least, the vast majority of people will point out that their close contacts are already as low as they can possibly be, and so there is little opportunity to reduce them further. Indeed, people will say that it has been like this for months.

We do know that the average number of close contacts has been falling. HSE Chief Executive Paul Reid recently said that the average number of close contacts per person had fallen from 4.5 to 3 on average;I don’t think we know the standard deviation on this though, so there may be a significant number of people with many more close contacts than this average. In any event, this will not continue if and when we exit Level 5.

One of the problems is that there is reason to believe that we may not have an accurate sense of our own close contact reality, at least outside of lockdown. I think that the majority of us feel that we have reduced our close contacts to a minimum, but can we be impartial in this assessment?

The Lake Wobegone Effect

I am reminded of a famous study by a Swedish psychologist named Ola Svenson in which, he asked 81 American college students and 80 Swedish graduate students to rank their driving ability among their peers. The results were striking because 93% of the Americans and 69% of the Swedes said they were better than average. Clearly, most people cannot be better than average and, therefore, there must be many people who are convinced that they are far better drivers than they really are.

Several other studies have reached similar conclusions about our tendancy to overestimate our own abilities. For example, in one 90% of college professors rated themselves as above average lecturers or teachers, while another found that only 1% of 800,000 high school students viewed their social skills to be below average.

Psychologists refer to this this cognitive bias as illusory superiority — the tendency of a person to overestimate his or her own qualities and abilities, in relation to others — although it may be better known to some as the Lake Wobegon Effect, after a US radio show which was set in the fictional town of Lake Wobegon, where “all the women are strong, all the men are good looking, and all the children are above average.”

What might it mean if we held similar views about the number of our close contacts? We might think they are low but they might not be. We might assume that we are doing better than our peers when we are not. At the very least, this cognitive bias could undermine our ability to live safely with the virus outside of strict lockdown, and it might lead us to point the finger of blame towards others if things don’t go well.

One of the challenges in this regard is the lack of personalised evidence about how we are doing as individuals. We have to rely on our intuitions, which may be faulty. Certainly, the aggregate data we do have, in the form of case numbers, tells us that we were not doing as well as we needed to in September and October.

Screen Time for COVID Close Contacts

Unless we attend to this we will not be able to exit Level 5 safely and we are heading for a repeat visit to lockdown in January. So what can be done?

The good news, I think, is that the problem bears all the hallmarks of an information problem. In other words, it might be solved by providing people with accurate information about their own behaviour to help them better understand the reality, rather than relying on their biased intuitions. And by providing people with this type of information, we can potentially help them to recognise issues and perhaps even nudge them in the right direction to improve their behaviour. How might we do this?

Apple’s Screen Time reports are a good example of what I have in mind. Every week my iphone/ipad generates a screen time report — similar to that shown here — which tells me about how much screen time I have had, and how it was distributed by time (day of week and hour of day) and by app or app category (social media, productivity, entertainment etc.). It tells me whether I have had more or less screen time than previous weeks and I can use these reports to track my progress, calibrate my device usage, and even to set goals/limits if I wish to moderate my screen time.

The point is that this type of approach eliminates the guesswork by replacing it with data. It forces me to confront the reality of my screen time instead of hiding behind my own potentially biased intuitions. And it helps my family to get a better sense of how much time we are all spending on our devices during the week.

A few weeks ago this I found myself wondering whether it might be possible to generate analogous Close Contact Reports so that we could all more accurately monitor our day to day interactions and ensure that our intuitions line up with the reality. The existing COVID tracking app seems to be well-suited to providing exactly this type of functionality, because it already has the ability to (anonymously) track our close contacts for contact tracing purposes, and so it is ‘just’ a matter of converting these existing data into some form of summary report.

Please excuse my graphic design (in)abilities, but below are two example screen-shots of what I have in mind. Each one shows a different view of a close contact sumary report.

The left-hand screen-shot shows yesterday’s close contact summary. The bar graph, indicates the number of unique close contacts during different parts of the day, and these close contacts are classified as regular (e.g. family members, work colleagues for those who are unable to work from home, class mates and teachers etc.), occasional (perhaps friends that we meet occassionally but not daily) and new (contacts that the app has not seen before or that are rare in a given period). The right-hand image shows a similar view, but this time for the previous week. We can see how, on most days, our close contacts remained low and stable (probably family members only) but on Wednesday, Saturday, and Sunday they peaked; perhaps this is something to focus on for the coming week?

The point is that this provides us with real numbers about our close contacts which is one way for us to calibrate our behaviour as we emerge from stay-at-home Level 5. Our close contacts will likely increase significantly during this transition and we will all need to keep on top of this if we are to have any hope of containing transmission.

Each screen-shot also shows additional information about how the number of close contacts we had yesterday, or last week, and compared with the close contacts of our peers. For example, we see that yesterday’s close contacts were 25% higher that the average for our age group; the dial off-screen shows a similar comparison but based on our location (town, electoral district, or county, for example). This helps to put our behaviour in context and may be an important way to nudge people in the right direction. For example, it may help parents to agree more realistic close contact expectations with their teenage children.

As an added bonus this type of functionality might help to drive further adoption of COVID apps. We know all to well that apps need a ‘hook’ to bring people back on a regular basis and the best bait to use on this hook is something that appeals to our ego, especially something that compares us to our peers. So by implementing a close contact report we can create a reason for people to check use the app at least daily, raising its profile in the community, and driving its adoption.

The current COVID tracking app in Ireland is perhaps a little stuck at 1.3m active users, with tends of thousands of checkl-ins per day. The question is how we can get this to 2–3m active users with millions of check-ins per day; such usage has the potential to seriously move the contact tracing needle. I’m not saying a close contacts report is the answer but it may be part of the answer, while at the same time provided key functionality for users to help them live more safely wuith the virus.

The Problem of Rotating Identifiers

There is one technical issue with the above. When a COVID app registers a contact with another phone/device it associates this contact with a unique identifier. But to maximise privacy it changes these identifiers every 15 minutes or so. This can mean that the same extended contact can be associated with multiple ids, which may lead to an incorrect close contact count, especially for long-lasting contacts. For example, in the home or in an office, persistent close-contacts may appear multiple times.

Even if this is the case it should still be possible to communicate useful information, at least in terms of relative differences in close contacts, if not the actual counts. For example, it is useful for a user to understand that their close contacts today are higher or lower than their close contacts one the same day a week ago, and the relative difference between the close contact (over) estimates may accommodate this if the nature of the over-estimates remains relatively consistent. And as the weeks go on these relative differences should become more and more accurate. In fairness, this may mean it is not possible to categorise contacts as regular, occassional, or new but once again, at this point its about the relatives differences.

Conclusions

The point I want to make in this article is that although we are doing very well in Level 5 — cases are falling steadily and hospitalisations have stabilised — the real test will occur when we exit Level 5 into the silly season of Christmas. The danger is that we will all lower our guards — some more than others — and transmission rates will silently grow until it is, once again, too late to stop infections from exploding. If that happens, then we may have no choice but to drop back into lockdown sometime in January.

While clear and constructive advice from health officials is necessary to live safely with the virus, we already know that it is not sufficient; after all we ended up in lockdown for a second time despite a comprehensive living with COVID plan. As individuals, we need more targeted information. Only then can we overcome our in-built cognitive biases, which serve to undermine our ability to live safely with the virus.

The good news is that we can do this. We can provide targeted information to millions of people via the COVID app, and in a way that can help them to better understand their own close contact reality, and to provide the means to do something to improve it. It may help families, parents and children, to more openly discuss their behaviours and highlight some hard-truths about what the data says.

There is no point in hiding from this data, especially if doing so lulls most of us into a false sense of security that we are better than average. Instead, we may as well surface the data so that we can learn from it and act on it. Then we have a shot at living more safely with the virus, especially if we continue to follow all of the other advice too.