I have been debating whether I should continue writing about what is already on all of our minds, or if I should focus my attention on positivity and humor. The latter is hugely important at a time like this, which is why I have been trying to intersperse my thoughts, both here and on Twitter, with things like funny videos, dance music, and architecture.

But the reality is that none of us know how this is all going to play out. As I mentioned yesterday, very few of us have a mental model for this kind of macro event. So it's important for all of us to continue learning. Is our country taking the right approach? Are we doing enough? How long are we going to have to live like this and what does that mean for the global economy?

The Financial Times published an invaluable story earlier this week about a small town outside of Venice called, Vò. With only 3,300 people, the town was supposedly able to test and retest all of its residents while the rest of northern Italy was growing as an epicenter for the Wuhan virus.

In late February, they completed their first round of testing and found that about 3% of the town had been infected. But it's important to note that about 50% of those that were infected were completely asymptomatic! However, because everyone was tested, the asymptomatic people got immediately quarantined.

The town did a second round of testing about 10 days later and that point the infection rate had dropped to about 0.3%. Of course, if all those asymptomatic people had been out and about in the town of Vò, this would not have been the case. There now appears to be no new cases in Vò.

It is for this reason that the WHO is urging diligent and repeated testing. But that obviously needs to be done in a sensible way. Having people line up -- together -- for hours upon hours is an obvious problem. Most people are not getting tested.

Earlier this morning, San Francisco-based Nurx announced a home testing kit for the Wuhan virus. Supposedly it is the first of its kind in the US. (It's not yet available in Canada -- I asked). I don't know how available it is to Americans or how accurate it is, yet, but I do know that something like this needs to become widespread.

The Financial Times published the following chart last night. It shows the cumulative number of COVID-19 cases around the world, across the number of days since the 100th case in that particular country. The message here is that most western countries appear to be on a similar trajectory. (The grey dotted line represents a 33% daily increase.) Whereas in Asia, and in particular Hong Kong and Singapore, they have seemingly managed to slow the spread.

Now, there are a number of possible explanations for the outliers; everything from stricter quarantine rules to more rigorous testing. There's also an argument that Hong Kong and Singapore were better prepared as a result of the SARS outbreak in 2002. (More on these explanations, here.) But the other factor at play seems to be climate.

A recent study (by Jingyuan Wang, Ke Tang, Kai Feng, and Weifeng Lv) has concluded that, like the flu, the transmission of COVID-19 appears to be significantly impacted by both air temperature and relative humidity. In their research, they looked at the reproductive number (R), or the severity of infectiousness, for all Chinese cities with more than 40 cases between January 21 to 23, 2020. (Large-scale government interventions began on January 24, 2020 and would have therefore skewed the numbers.)

What they found was that for every one degree Celsius increase in temperature and every one degree Celsius increase in relative humidity, the reproductive numbers drop by 0.0383 and 0.0224, respectively. Air temperature, in other words, has more of a positive impact on containing spread than relative humidity -- which feels right. That is also apparent when you look at the above charts. Take note of Korea, Iran, and Italy near the top left corner of the temperature chart.

If you'd like to download a full copy of the research paper, click here.

This recent paper by Miyuki Hino (University of North Carolina) and Marshall Burke (Stanford) makes the case that US homes situated within floodplains are currently overvalued by a total of $34 billion. And that's because the associated risks are not being properly accounted for in the value of these homes.

The problem, it would seem, comes down to information. Because the discount for flood risk was found to be higher (1) for commercial buyers (presumably because they're more sophisticated and/or have better access to information) and (2) in states where sellers must disclose flood risk (Louisiana is probably the most stringent about this).

This feels a bit like one of those realtor commercials that tries to scare you into using one. But it does appear to demonstrate just how opaque the market can be and how information asymmetries potentially distort asset prices. Perhaps most importantly, I wonder when climate risk will get fully valued.