Recent News
Wake County Omicron Mortality Rate
I’ve seen many articles on the mortality rate of Covid-19, either nationally or globally, but what I haven’t been able to find is the mortality rate of the Omicron variant for the county I live in, which is a much more relevant piece of information.
Now before we get into what I found, here are some caveats:
I am not a doctor. I am not a virologist. I am not a statistician.
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2022
Polarization I pretty much nailed all my predictions for 2021, in particular I wrote about right-wing extremism:
I fully expect Trump, unconstrained by the people that surround him in the White House today, to become even more unhinged and try to inspire even more violent acts of terrorism."
I wrote that two weeks before Jan 6th.
I also wrote about the roots of that violence as a loss of power:
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Perfetto SPAN_JOIN and LEAD Explained
Perfetto and the SQL processing built into trace_processor are both fantastic, but two of the most important parts of that SQL processing are not well documented, at least for my simple brain.
The first feature is SPAN_JOIN which is described as:
Span join is a custom operator table which computes the intersection of spans of time from two tables or views.
There is a nice diagram showing how the spans are combined:
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Random Integer Matrices With Inverses That Are Also Integer Matrices
I want to generate a random integer valued \( n \times n \) matrix \( A \) whose inverse is also an integer valued matrix, i.e. how can I generate Unimodular matrices?
The key is starting with an \( n \times n \) identity matrix \( I \), which has a determinant of 1. Then you can apply row operations to \( I \) that keep the determinant 1, i.e. by picking row operations that are expressible as multiplication by a matrix that also has a determinant of 1 with integer components.
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The Seeds of Delusion
Remember that nauseous feeling you had on waking up on Nov 5, 2016 to a Trump presidency? For me, the root of that nausea was the dawning realization that a majority of my fellow Americans were deeply racist, or at least there was enough of them to propel Trump to the highest office in the land.
I’m not naive, I always knew there were racist people, but I presumed they weren’t a majority, they were a minority, and a shrinking minority at that.
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