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Monthly Archives: January 2011
Why recommendation engines matter
“The Internet makes everything available, but mere availability is meaningless if the products remain unknown to potential buyers.” (possibly attributable to Gavin Potter, a Netflix Prize contestant; possibly to Jordan Ellenberg, who writes for Slate and Wired)
Movie Ratings
Another unmeasurable distance is ★★★ movie ratings. Movie ratings are drawn from the set {★,★★,★★★,★★★★,★★★★★} and related by the total ordering >: ★★★★★ > ★★★★ ★★★★ > ★★★ ★★★ > ★★ ★★ > ★ and the transitivity of > gives … Continue reading
Posted in Uncategorized
Tagged abstract algebra, Amos Tversky, distances, film, isomorphism, math, mathematics, maths, metric spaces, metrics, movies, Netflix, recommendation engines, topology
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Smoking in Bars
You know how there are smoking bans in various bars, pubs, and restaurants? How can the government do that? I mean, the location belongs to the proprietor. You know? edit: I know why they do it — I just mean, … Continue reading
The Hotness Scale
One example of a total ordering ≤ is the “hotness” scale from 1–10. Because of the widespread disagreement about the meaning of the numbers, the only thing one can infer based on a man’s rating of a woman is that … Continue reading
Posted in Uncategorized
Tagged attraction, boys, comparable, distance, geometry, girls, hotness, LGBTQ, liking, math, mathematics, maths, measures, metric, metric spaces, metrics, norm, norms, partially ordered set, partially ordered sets, poset, posets, quantification, sex, sex appeal, sexiness, size
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Unmeasurable Distances
I wrote earlier about the many different ways to measure distance. One way I didn’t include is unmeasurable distance. Sometimes A is tastier, sexier, cooler, more interesting, or otherwise better endowed than B … but it’s impossible to quantify by … Continue reading
Posted in Uncategorized
Tagged comparable, distance, economics, education, geometry, imagination, math, mathematics, maths, metric, metric spaces, metrics, norm, norms, philosophy, preference, preorder, rank, ranking, size, total order, unmeasurable distance, utility
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wowgreat: 95988NebelWald_rund2_23 (by holger lippmann) (Source: http://www.flickr.com/photos/lumicon/5373315597/#/photos/lumicon/5373315597/lightbox/)
Theory is easy. Data are hard. Bill Becker 1 2
Quote
January 25, 2011
Tagged data, econometrics, education, facts, heroes, LimDep, math, mathematics, maths, statistics, theory
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Lawyers enable complex laws
Let’s assume that (i) there is an optimal number of lawyers and that (ii) said number is between 0% and 100% of the population. The cost of adding a lawyer to society is that a smart, articulate person no longer … Continue reading
Posted in Uncategorized
Tagged accountants, ¡, cost of implementation, economics, education, James Mirrlees, lawyers, Mirrlees, negative sum game, SarbanesOxley, tax, transparency
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wowgreat: 88850FlowerCircles_13_grid1 (by holger lippmann) (Source: http://www.flickr.com/photos/lumicon/3643026707/in/set72157619962429652/)
In this paper an exhaustive characterization of financial markets was given. Dependence: Autocorrelation in returns if largely insignificant. (Exceptions being at the tick level and annual returns.) Distribution: Approximately symmetric, increasingly positive kurtosis as the time interval decreases and a … Continue reading