Is now a good time to point out that this bet can be thrown?
As in I could deliberately infect myself or some other member? Sure, but I'm not gonna do that for 30 euros and I think my opponent doesn't expect me to.
If I was that type of person, and ignoring all social, ethical and legal consequences of doing so... there are at least two factors making my expected payout from it lower than 30 euros, potentially even negative in combination:
When your first sample is from known liars and your second from people that fucked everything else up that doesn’t inspire confidence.
Sure, these numbers are obviously not very reliable. But:
Well, there’s a very good reason for that, isn’t there?
I consider this off-topic and I'd prefer it not to be discussed in this thread.
I occasionally make bets about future events. I think I probably should do that more often than I currently do. Given that, I think it's good practice to have a public record of the bets I've made and their outcomes, when available.
I'll try to keep this updated going forward, if I continue to make bets. (But only on my original blog, I won't copy the edits over to LW.) Currently I'm down £72.46 with one win and one loss.
(This has nothing to do with the matched betting that I previously wrote about. There I was earning money from sign-up bonuses. Here I'm trying to earn money by being better at predicting the future than other people.)
In order of date I made the bet:
I placed this bet on 20-Oct-2019, on Betfair, after a friend said on Facebook that the odds seemed very favorable to him. The odds at the time were 1.3, giving an implied probability of ((1.3 - 1) / 1.3 = 30%) that he'd leave. I bet £50 against this, giving me £15 profit if he doesn't. (Minus commission, so £14.25.) As of 19-Mar-2020 the odds are 1.12, for an implied probability of 11% that he'll leave. (I could cash out now, taking my £50 back immediately and £7.56 minus commission when the market closes[1]. I'm not inclined to do that.)
LessWrong user Liron said:
I also bet more than 50% chance that within 3 years at least one of {Google, Microsoft, Facebook, Amazon} will give more than 50% of their software engineers the ability to work from home for at least 80% of their workdays.
I took him up on this for $100 each. We confirmed on 02-Jan-2020. I don't think I'd heard the term "coronavirus" at the time.
This cost me $100 (£92.69 over Paypal, which I think included £2.99 transaction fee). But I got a bunch of LW karma for it. Swings and roundabouts.
In a Telegram group chat I'm in, I bet another member €30 each that at least one person in the chat would contract Covid-19 by 28-Feb-2021. (We made the bet on 28-Feb-2020.)
I wasn't confident of winning at the time, and I'm still not. Confirmed infection rates are lower than I'd anticipated - for example, Hubei has had just over 0.1% of its population confirmed as having had the disease at one point, and Italy just over 0.05%.
I think an ambiguous result is more likely than I used to, because people who get mild cases of the disease often aren't tested.
On 04-Mar-2020, I noticed that the betting markets' odds on Trump's re-election had gone up since Covid-19 became a thing. (According to Election Betting Odds, rising from about 40% mid-november to about 56% at the time.) At the time, the number of officially diagnosed cases in the US was very small. I predicted that as the official number rose, and as it became more widely known that the CDC and FDA had basically fucked up, the odds would drop again.
The obvious objection was: "if you can predict that happening, so can anyone. Why haven't the odds changed already?" I didn't have an answer for that, but the stock markets had seemed to react slowly to the news[2] so maybe it would happen here too. (And the next obvious objection was: "oh, so you're expecting the same thing to work twice in a row?" I didn't have an answer for that either.)
Less obvious objections that I realized/someone pointed out after I'd made the bet:
In any case, I went ahead. Again on Betfair, I bet £100 against Trump at odds of 1.76. The odds started to drop pretty soon after that. Two weeks later, on 18-Mar-2020, I cashed out (by betting £110.26 for Trump at odds of 2.1, but actually by pressing the "cash out" button). I've claimed my initial £100 back, and no matter who wins I'll earn £21.29. (£20.23 after commission, but nothing if the market is voided.)