another episode of Youtube waltz watch

挥一挥衣袖，不带走一片云彩 (I wave my sleeves. Not even a wisp of cloud will I bring away) Chua Lam, the beloved food critic and cultural icon based in Hong Kong, passed away today. His deep love for food went beyond appetite—it shaped a way of living. A philosophy that was unique, profound, popular, and deeply worth remembering. Rest in peace. Wish heaven (or anywhere you’re in) have great food. ...

I designed a beamer latex template. Here’s the overleaf link and here’s the demo pdf. See the pdf for other pages of the demo. Design idea: Use the Poppins typeface — it’s a round, sans-serif font. (an open-source substitute for Google’s beautiful proprietary font Product Sans). (See Google Fonts: Poppins for details. Color: black text with pink accent on light-beige background. Minimalistic functions: I disabled navigation toolbar and the page that list references. Beamer is really useful when one want to make slides quickly. It’s well-formatted — Latex’s automatic spacing frees you from the annoying chore of aligning text boxes. And you can write math-heavy paragraphs easily. ...

I’m graduating tmrw :) For this coda chapter, I really want to play this music for myself: Vivacious tempo, sparkling technique, bursting with joy, somewhat hidden, and adds a little bit obsession over details and perfection — this piece really best summarize my undergrad journey. What piece would you choose as your graduation day bgm?

The paper “Approximation Algorithms for Restless Bandit Problems” by Guha, Munagala, Shi (2009) designed a $2 + \epsilon$-approximation algorithm for a special class of RMAB (“Feedback MAB”, and generalized to “Monotone MAB”). The algorithm is fundamentally different to the classical Whittle Index. The paper’s analysis uses a duality-based algorithmic technique—it is vastly different compared with Weber (1988)’s proof for RMAB’s asymptotic optimality, hence the $2 + \epsilon$ approximation outcome doesn’t requires asymptotic. ...

There’s no gene for the human spirit. — Gattaca (1997) Vincent Freeman is born into a genetically engineered society but conceived naturally, deemed ‘in-valid’ due to a heart condition. Determined to defy his genetic fate and reach space, Vincent assumes the identity of Jerome Morrow, a former elite athlete, to join Gattaca’s space program. ...

The visible world is no longer a reality and the unseen world no longer a dream (Kandinsky)

This is beautiful, beautiful, beautiful!

Evoking the rush of water, the stroke of oars and the motion of the ocean, the Barcarolle was a folk song sung by Venetian gondoliers (the word comes from “Barca” meaning “boat”). Characterised by a rocking rhythm, suggestive of the movement of the gondola, a Barcarolle is usually of moderate tempo scored in compound time (often 6/8, 9/8 or 12/8). The genre has been used by many composers to great expressive effect. ...

Multi-armed bandits with switching costs are a special case of the restless-bandit model. Setup Consider the infinite-horizon, discounted MAB problem with finite state space $\mathcal S$, binary action set $\{0,1\}$ per arm ($1$ = pull, $0$ = idle), discount factor $0\le\beta<1$, arms evolve only when pulled (i.e. “static” when $a_i=0$), per-pull reward $r_i(s)$. We now add two costs for each arm $i$: switch-in cost $c_i$: paid (once) whenever we switch to arm $i$, ...