ariana's blog

how to customize font on my website?

ChatGPT makes it much easier to modify configurations for my website. I changed the font to Montserrat—an open source font provided by Google font (fonts.google.com) that is highly similar to Google’s proprietary logo font Product Sans. Well cause: Google Sans [and Product Sans] is not available for use outside of Google. It is our brand font and is exclusively used in Google products. Fine. Fonts provided and maintained by Google font has a delivery service—everytime the website loads, it fetches font files from Google. So that only a few lines are required to do the customization. Find embedding code from, for example, https://fonts.google.com/selection/embed, and put the following in <head> of HTML layouts/_defaults/baseof.html ...

mechanism design seminar notes | week 5

Something interesting happened in today’s seminar course. One of my classmates presented his final paper, and as expected in a seminar setting, our instructor, Hu Fu, wants everyone to stay engaged and understand what’s being discussed. Today’s presenter had clearly prepared and read the paper but had no clue how to structure an academic talk. He skipped all the basics—no background, no context of the model provided—and jumped straight into the technical details. Naturally, no one understood a thing. So after the first few minutes, most of the audience zones out, especially once the technical parts hit. ...

mechanism design seminar notes | week 4

Motivation Preview from problem set 2, question 4: (link to original file) This gives a reduction: [submodular welfare maximization] <= [maximize a monotone submodular function s.t. matroid constarint]. Remarks: hardness & approximation of the problem [submodular welfare maximization] >= [maximize a monotone submodular function s.t. matroid constarint] (Is it true though?). maximize monotone submodular function is hard. Because, for instance, one can reduce Partition problem to it. That’s why we started looking at submodular maximization s.t. matroid constraint in last week. To begin with, ...

the Buy Box Bubble — some thinkings

Following the news of Amazon’s lawsuits and after skimming through the complaints, here are my thoughts. price do go up | 羊毛出在羊身上 There’s no free lunch. While prices may seem lower on Amazon, the market is interconnected. Amazon’s attempt of achieving lower price would backfire. Amazon’s power forces sellers to comply with its Buy Box rules, meaning they must keep prices equal or higher across all channels to access Amazon’s vast demand. However, because Amazon charges high commissions, sellers often decide to raise prices across the board. ...

the Buy Box Bubble — what does the complaint reveal about the Buy Box

Following yesterday’s coverage on Amazon’s series of trouble with antitrust regulators, I digged into the filing complaint of CA v Amazon and the orginal complaint and amended complaint of FTC v Amazon. We can obtain quite a bit of interesting information about Amazon’s Buy Box: (at least, from the perspective of regulators…) first, Amazon chose to make purchasing outside the Buy Box hard: Nearly 98% of Amazon sales are made through the Buy Box. ...

the Buy Box Bubble — Lawsuits!

Here are recent news about Amazon Buy Box’s into antitrust trouble: California sues Amazon | September, 2022 Timeline: Sept. 2022: Attorney General Bonta sued Amazon in the Superior Court of California. The lawsuit basically focused on accusing Amazon penalizing sellers for listing products at the lower price on other selling channels—that if Amazon spots a product listed elsewhere cheaper, it will often remove the seller from the Buy Box on Amazon. ...

pending subjects...📋

people in academia are generally too good at procrastinating. doing things at last minute isn’t entirely wrong. like, some job scheduling algorithms do look like they are procrastinating. plus there is the infamous structured procrastination… but at the end of the day, procrastination makes one think inefficiently in a rush, raise anxiety level and occasionally, blow up deadlines. so here’s an effort of trying to battle my procrastinating tendency during bloggings: ...

mechanism design seminar notes | week 3

Recap of week 2, and motivation for this week’s Part I: In an economy of $n$ agents and $m$ indivisible items, if all agents’ value functions are Gross-Substitute, the economy has a Walrasian Equilibrium $(\vec S, \vec p)$. The Walrasian Tatônnement process can find the equilibrium efficiently. The allocation also maximizes social welfare. But one subtle thing to notice about Walrasian Tatônnement is that it converges to an equilibrium. So here’s another way of solving it: ...

Nobel Prize in Chemistry, or Computer Science?🤦🏻‍♀️🤦🏻‍♀️🤦🏻‍♀️

👏🤦🏻‍♀️👏🤦🏻‍♀️👏🤦🏻‍♀️ 50-years of open problem closed. Proteins are essentially correctly folded and well-functioning polypeptide chains. So theoretically, protein 3D structures are determined by the sequence of amino acids in the polypeptide chain. The Nobel Prize in Chemistry (1972) was awarded to C. Anfinsen for this finding. amino acids make up proteins essentially like LEGOS. importantly, proteins function only when they are folded and form their structure in the right way ...

Nobel Prize in Physics, or Computer Science?

Much to almost everyone’s surprise, the Nobel Price in Physics 2024 is awarded to John Hopfield and Geoffrey Hinton, for their foundational discoveries and inventions in ML: When we talk about artificial intelligence, we often mean machine learning using artificial neural networks. This technology was originally inspired by the structure of the brain. In an artificial neural network, the brain’s neurons are represented by nodes that have different values. These nodes influence each other through connections that can be likened to synapses and which can be made stronger or weaker. The network is trained, for example by developing stronger connections between nodes with simultaneously high values. This year’s laureates have conducted important work with artificial neural networks from the 1980s onward. ...