## Georgia on my mind

Posted in Books, Kids, Statistics, Travel with tags , , , , , , , , on May 12, 2021 by xi'an

The riddle of this week was inspired by the latest presidential elections when one State after another flipped the winner from Trump to Biden. Incl. Georgia.

On election night, the results of the 80 percent who voted on Election Day are reported out. Over the next several days, the remaining 20 percent of the votes are then tallied. What is the probability that the candidate who had fewer votes tallied on election night ultimately wins the race?

Assuming many votes, perfect balance between both candidates (p=½), and homogeneity between early and late ballots, the question boils down to the probability of a sum of two normals, X+Y, ending up being of the opposite sign from X, when the variances of X and Y are α and 1-α. Which writes as the expectation

$2 \mathbb{E}_\alpha[\Phi(-X/\sqrt{1-\alpha})]$

equal to

$\frac{2}{2\pi}\left(\frac{\pi}{2} + \arctan\{\sqrt{\alpha/(1-\alpha)|}\}\right)$

which returns a probability of about 0.14 when α=0.8. When looking at the actual data for Georgia, out of 5 million voters, at some point 235,000 ballots remained to be counted with Trump on the lead. This means an α about 0.05 and implies a probability of 7% (not accounting for the fact that the remaining mail-in-ballots were more favourable to Biden.)

## M cover

Posted in Books, pictures, Travel with tags , , , , , , on January 17, 2021 by xi'an

## it was the spring of hope, it was the winter of despair

Posted in Kids, Travel with tags , , , , , , , , , , , on January 16, 2021 by xi'an

## it was the best of times, it was the worst of times

Posted in Books, pictures, Travel with tags , , , , , , , , , , , , , , , on January 7, 2021 by xi'an

## The trouble with peace [book review]

Posted in Books with tags , , , , , , on December 26, 2020 by xi'an

This is the second volume of Joe Abercombie‘s The Age of Madness trilogy, which takes place (as usual) in a renaissance-like universe, except it now comes with Da Vinci’s like industrial innovations starting to disrupt its medieval social order (and the role of magic, almost gone) and making this admittedly ugly cover relevant. (Just like the rich quotes and titles from his previous books, Abercrombie is demonstrating a serious grasp of literature, since the title comes from a line of Bertold Brecht: “You know what the trouble with peace is? No organization.”)

“Enemies are like furniture, aren’t they? Better chosen for oneself than inherited.”

This book is just as good as the previous one, if a bit slow in building its climactic battle and somewhat predictable. The characters are as formidable as previously, if facing steep odds and declines of fortune, with hilarious scenes and dialogues (as always with Abercrombie), including some pastiches of Trumpian talks. And a more serious take on the standards of the genre, with workers becoming a revolutionary force ready to overthrown the antiquated power structure. Looking forward the last volume, planned to be published a year from now.