Food: Peanut butter and Nutella digestives
This is becoming my usual afternoon tea during the past few weeks of working from home. Probably more than compensates for my daily run and exercises. Will need to get back to healthier habits soon. Perhaps only one piece per day in the coming week?
Love: Spring is here!
Since spending more time at home, my wife has been able to give more attention to our potted plants. The love and care is paying off – our balcony is more colorful than a couple of weeks back.
Growth: Trying to be a better father
I’ve been reading the book How to Raise an Adult by Julie Lythcott-Haims, a dean of freshmen and undergraduate advising at Stanford University. I’m still at Part 1 where the author elaborates on the many ways modern-day parents are robbing their children of opportunities to grow and become independent. The author mentioned examples of hyper-vigilance in pre-schools up to universities, and parents exerting their ideas of ‘best’ on their offspring. In this respect, there’s not much difference between Western and Asian parents.
One of the problems parents encounter is – how can they help both their kids and the teachers better, by monitor their children’s submission of school work? This prompted me to look at Google Calendar’s reminders function as a potential solution. In a roundabout way, it also prompted me to think about linking the forgetting curve with the reminder function. This function is currently quite static in Google Calendar – reminders can be set a fixed number of occurrences spaced at regular intervals apart, e.g. weekly or monthly. However, to properly mitigate the impact of forgetting curve, one would want to schedule the first revision two days later, the second revision a week later, the third ten days later, for example. I also looked at using IFTTT to create an applet to trigger entries in Google Calendar. However, this is very cumbersome – entries need to satisfy fixed syntax, and I’ll need to create multiple applets to cater to different reminders. Perhaps Google can make some tweaks to the Reminder function?
Investment: Equities markets trajectories during crises
A friend asked me for a chart on the trajectories of the equities market during the various crises over the past few decades. Here’s what I was able to put together for the SPX:
Black Monday 1987 day 1 was 1987 Oct 16th. The next trading day was the notorious Black Monday 1987 Oct 19th. SARS 2003 was essentially an East Asian crisis, with day 1 on 2003 Mar 17th, when WHO released its first situation report. GFC 2008 was global, with day 1 on 2007 Oct 9th, when SPX peaked at 1565. COVID-19 is another global affair, with day 1 on 2020 Jan 20th, when WHO released its first situation report.
My previous week’s thesis on wheat prices has not worked well this past week. Price closed 4% down compared with last week. I looked at data back to 2010 Jan for occasions when prices dropped 4% or more week-on-week. There were 83 such occasions. I then look at price changes over the two weeks on such occasions. It turns out that prices increased on 45 of these 83 occasions (54%) over the next two weeks. The average price gain on such positive gains occasion was 5.3%. The corresponding figure for negative price change occasions was -4.6%. This gives an average expected return over 2 weeks of 0.7%.
I also looked at what would happen after 1 week and 3 weeks. The two weeks horizon seems optimal to me when trying to balance the probability of win and limiting the extent of potential loss. Here is the summary:
Awe: Non-linearity of carbon dioxide
This month’s issue of the Smithsonian featured a question from a reader asking about the effect of climate change on space junk such as outdated satellites or spent rocket stages.
The response was a good reminder of the non-linearity of nature. It turns out that carbon dioxide behaves differently in different parts of the earth’s atmosphere. In the troposphere, the lowest part of Earth’s atmosphere, carbon dioxide traps heat – hence temperature rises on the Earth’s surface. In the thermosphere, however, where most of the man-made orbiting objects are located, carbon dioxide releases heat into space and chills this upper layer of atmosphere. As a consequence, the thermosphere contracts, resulting in less atmospheric drag or friction on space junk.