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Chinese are always serious and obsessed about food. On the 26th birthday of Alibaba (2025 Sept 10), AMap released a new Local Discovery Ranking (扫街榜) — for restaurant and general local service recommendations. Unlike traditional online rating platforms rely mainly on user ratings, AMap uses behavioral data including navigation usage, in-store visits, repeat visits, and intentional destination trips to make the rankings more authentic, trustworthy and immune to score manipulation. AMap’s CEO Ning Guo (郭宁) pledge that the rankings would “never be commercialized”: ...

Prokofiev composed the Flute Sonata (Op. 94) between 1942-43. Though it is commissioned, he like flute (thankfully) and probably had poured his personality all over the piece — “I had long wished to write music for the flute, an instrument which I felt had been undeservedly neglected.” In 1943 Prokofiev adapted few changes for bowing to transcribe a version for violin. Ah, the long tradition of flutist and violinist stealing each other’s repertoire. ...

Mencius was a famous Chinese philosopher (Mengzi, 孟子), a major follower of Confucius who lived during the Warring States period (roughly 4th century BCE). There’s a historical legend that Mencius’s mother moved house three times to find a better environment for his education. Acient wisdom of explained by modern economic: Neighborhood Effects and the Missing Market for Opportunity Lawrence Katz (Harvard) | 2026 Jan 2 Watch the full AEA 2026 President Address here ...

A reddit user who claimed to be an engineer at a major food delivery platform talked about why he doesn’t enjoy working there. TL;DR: a lot of intransparency, fees and tips don’t got to driver, sludge, etc. Particularly, I find the following desperation score to be quite a bad idea: The “Desperation Score”… a hidden metric for drivers that tracks how desperate they are for cash based on their acceptance behavior." ...

An interesting paper to read and understand how to get more citations: Nonuniversal power law scaling in the probability distribution of scientific citations Peterson, Pressé and Dill (2010) PNAS ABSTRACT: We develop a model for the distribution of scientific citations. The model involves a dual mechanism: in the direct mechanism, the author of a new paper finds an old paper A and cites it. In the indirect mechanism, the author of a new paper finds an old paper A only via the reference list of a newer intermediary paper B, which has previously cited A. By comparison to citation databases, we find that papers having few citations are cited mainly by the direct mechanism. Papers already having many citations (“classics”) are cited mainly by the indirect mechanism. The indirect mechanism gives a power-law tail. The“tipping point” at which a paper becomes a classic is about 25 citations for papers published in the Institute for Scientific Information (ISI) Web of Science database in 1981, 31 for Physical Review D papers published from 1975–1994, and 37 for all publications from a list of high h-index chemists assembled in 2007. The power-law exponent is not universal. Individuals who are highly cited have a systematically smaller exponent than individuals who are less cited. ...

On the Waterfront (1954) is an epic movie. Its soundtrack is composed by Leonard Bernstein and is nominated for an academy award (the movie won 8 in total). Source: Wikipedia. Impressive, right? Interestingly, the opening main motif of the soundtrack has a repeating theme (listen below) ♭B-♭A-B—F— Which sounds extremly like the Russian mournful folk song (start from 22s):

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My sister lives in north of atlanta. During Christmas holiday, our family drive into malls and malls through highway exits. Stability in Competition Harold Hotelling (1929) The Economic Journal | link In this paper, consumers are uniformly distributed along a line (a street, beach, political spectrum). Location is the only dimension of differentiation. There are two firms and each firm chooses a single location on the line. Entry and exit are ignored. Consumers buy from the firm that minimizes price + transportation cost. Every consumer buys from one of the firms; there is no opting out. Transportation cost increases linearly with distance. Either prices are exogenous or competition forces them to be identical, so location is the only strategic variable. ...

Here’s an interesting paper answering an interesting question where the answer can potential piss off a lot of people: Skill levels and gains in university STEM education in China, India, Russia and the United States Loyalka et al. 2021. Nature Human Behavior ABSTRACT Universities contribute to economic growth and national competitiveness by equipping students with higher-order thinking and academic skills. Despite large investments in university science, technology, engineering and mathematics (STEM) education, little is known about how the skills of STEM undergraduates compare across countries and by institutional selectivity. Here, we provide direct evidence on these issues by collecting and analysing longitudinal data on tens of thousands of computer science and electrical engineering students in China, India, Russia and the United States. We find stark differences in skill levels and gains among countries and by institutional selectivity. Compared with the United States, students in China, India and Russia do not gain critical thinking skills over four years. Furthermore, while students in India and Russia gain academic skills during the first two years, students in China do not. These gaps in skill levels and gains provide insights into the global competitiveness of STEM university students across nations and institutional types. ...

Shostakovich was popular and alright in USSR until 1936. Stalin attended several of Shostakovich’s opera and liked them, until Lady Macbeth. Stalin sat in the audience, cringed at loud parts of the score and laughed at sexual moments. Displeased, Stalin left after the end of the third act. A frightened Shostakovich was reportedly “white as a sheet” when he bowed for the audience. Two days later “Muddle Instead of Music” appeared on the third page of the 28 January issue of Pravda. ...