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2022-05-28 Links

Peregrine Soliton or Massive Waves

For centuries, scientists believed rogue waves were a myth, despite eyewitness accounts from returning mariners. The 19th century French explorer and naval officer Jules Dumont d’Urville made a name for himself as a botanist and cartographer, sailing around the world on various expeditions. Yet for all his fame and prestige, when Dumont reported seeing rogue waves over 100 feet high on his voyages, bolstered by three eyewitnesses who’d been with him, his claims were dismissed. Prime Minister Franҫois Arago publicly ridiculed him.

Bob Rudis Thinks Through Work and Play

Fans of observability know that a failing complex system may continue to regularly send critical event logs, but if nothing is reading and taking action on those logs, then the system will just continue to degrade or fail completely over time, often in unpredictable ways.After a bit more reflection, I realized that, at some point, I became Bill Murray, waking up each day and just repeating the last day, at least when it came to work.

Homelessness and Enforcement

Thus expensive housing and homelessness are linked, but not because the homeless can’t afford housing. Rather the correlation occurs because the homeless in expensive areas are not in the market for housing. For the homeless, the relative cost of living on the street in Los Angeles (relative to an apartment) is much lower than the relative cost of living on the street in Arkansas. So it would be rational for a homeless person to relocate from Arkansas to LA.

Key Rate Duration in R

Ho (1992) introduced the concept of the key rate duration (hereafter KRD), which is a new measure of interest rate risk exposure. KRD is a vector of the price sensitivity of a bond to each key rate change. The sum of the key rate durations is identical to the effective duration. The sum of the product of key rate durations and each yield changes in key rates (with negative sign) is the bond price change due to the non-parallel shift of the yield curve.

Carry and Roll in R

This post shows how to calculate a carry and roll-down on a yield curve using R. In fixed income, the carry is a current YTM like a dividend yield in stock. But unlike stocks, even though market conditions remain constant over time, the remaining maturity (life) is bound to decrease due to its maturity date. This makes so called the roll-down.

Pigeon Problem Rasperberry Pi Solution

After a quick burst of manic energy during exam phase, I decided to solve the pigeon problem on my balcony once and for all (and in a humane way). The idea was quite simple: Mount an electric water gun on my balcony, detect pigeons with a web cam and shoot them. Pigeons should not get used to getting sprayed at (at least not while its coldish), I don’t have to disfigure my balcony and I’m not harming the pigeons in any way or even risk killing them. As I approached this project during my exam phase, it should also be quick to implement using things I already have laying around.

Misidentifying Talent

The pessimistic view is that it seems implausible that we should expect that talent assessment is better than in sports, where it took decades of there being fairly accurate and rigorous public write-ups of performance assessments for companies to take talent assessment seriously. With programming, talent assessment isn’t even far enough along that anyone can write up accurate evaluations of people across the industry, so we haven’t even started the decades long process of companies fighting to keep evaluating people based on personal opinions instead of accurate measurements. – This post relates closely to this paper, a study of software engineers at Microsoft.