speaker: Guillermo Gallego | Prof., The Chinese University of Hong Kong-Shenzhen. TALK ABSTRACT: To study the limits of personalization, we introduce the notion of a clairvoyant firm that can read the mind of consumers and sell them the highest revenue product that they are willing to buy. We show how to compute the expected revenue of the clairvoyant firm for a class of rational discrete choice models, and develop prophet-type inequalities that provide performance guarantees for the expected revenue of the traditional assortment optimization firm (a TAOP firm) relative to the clairvoyant firm, and therefore to any effort to personalize assortments....

What an elegant name! It reminded me of the book Mostly Harmless Econometrics. Mostly OM is an annual international workshop sponsored by the School of Economics and Management, the Research Center for Contemporary Management, of Tsinghua University, focusing on the state-of-the-art research in Operations Management (OM), broadly defined. Mostly OM aims to provide a forum for researchers, from China and overseas alike, to foster interaction and exchange ideas, learn from each other new methodologies and applications, and explore opportunities for collaboration....

Andante cantabile(It.) is a direction often used by composers. In general, it means flowing and songlike. The andante tempo is known as the walking pace, and the pacing and energy should generally feel like a nice stroll. Cantabile [kanˈtaːbile], an Italian word, means literally “singable” or “songlike”. In instrumental music, it is a particular style of playing designed to imitate the human voice. To a large section of the public, however, it means one work, the 2nd movt....

Prologue In the highly competitive coffee market, a fierce price war erupted with the introduction of the ¥9.9 (~1.37USD) coffee, leading to dramatic changes for two major players: COTTI Coffee and luckin Coffee. Over the span of a year, this aggressive pricing strategy have caused COTTI’s slowing down in its pace of expansion, while luckin Coffee also saw its profits plummet, transitioning from profitability to significant losses. By Xu Qing | Edited by Jin Za...

Here’s a professional, in-depth intepretation of the Liederabend performance of Changyong Liao, originally in Chinese, available here. The program selected works from Italy, Germany-Austria, and China, each with distinct artistic themes. It included classic Italian art songs by Paolo Tosti such as “The Last Song,” “I Love You No More,” and “Melancholy,” totaling five pieces. The repertoire also featured twelve Chinese art songs, including “Three Wishes of the Rose,” “Spring Thoughts,” and “The River Flows Eastward,” as well as Gustav Mahler’s song cycle “Songs of a Wayfarer....

A two-day series on Lieder Today I had the privilege of attending a concert curated and performed by Changyong Liao, alongside his long-time collaborator, German pianist Hartmut Höll. The duo masterfully arranged a series of Lieder (aka, art songs) titled Three Wishes of the Rose: 16 Chinese Lieders. Witnessing these original composers interpret these songs was a profound experience, filled with a rich tapestry of emotions and beauty. The encore ’the seek of Prunus mume on a snowey day’....

Lieder in a nutshell The plural German noun Lieder (singular Lied) simply means “songs” – any kind of songs. But for classical music enthusiasts, the word signifies songs with piano accompaniment circa 1800–1900 – the birth of the form which coincided with the rise of the poetry-enjoying European middle classes in the wake of the French Revolution. Explainer: What Are Lieder? by Graham Johnson OBE. Lieder represents perhaps the most expressive sub-genre within classical music....

Working as a teaching assistant for college mathematics or general mathematically inclined courses turns out to be not as trivial a task as I’ve thought it to be. This semester I’m TAing for Advanced Optimization –– an obligatory course for sophomore students. I’ve also took last year. Moreover, I took an even more advanced version of it (convex optimization) while I was visiting Stanford last summer. Still, teaching and tutoring turns out not to be something that comes out of thin air....

Dynamic Programming (DP) serves as a foundational approach in computational algorithms, especially effective in environments with complete knowledge of state transitions and rewards, described within the Markov Decision Process (MDP) framework. However, the real-world often presents scenarios where such comprehensive information is unavailable. Here, Reinforcement Learning (RL) steps in with model-free methods that leverage DP principles but operate without the need for explicit transition probabilities or rewards. Markov Decision Process (MDP) Framework An MDP is a mathematical framework used to describe an environment in decision-making problems where outcomes are partly random and partly under the control of a decision-maker....

a stochastic calculus crash course for Financial Engineering. Building on Kolmogorov’s axiomatic probability theory, define continuous time stochastic process, for time $\mathcal T = [0,\infty)$ a sample path is essentially $$ {X_t : t\ge 0} $$ Brownian Motion History anecdote: In 1828, British Botanist R. Brown observed the random movement exhibited by plant pollens suspended in water. In 1905, A. Einstein proposed the first quantitative model of Brownian motion in terms of a Gaussian process, which explains some principles of molecular movements....