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Good news for the weekend? Increased Scrutiny Leads to an Improved Organ Transplant System NYTimes Background: a lot of things were problematic and NYTimes has been covering it, getting a lot of attention and debates: Organ Transplant System ‘in Chaos’ as Waiting Lists Are Ignored NYTimes Note: this article has pretty good data, and is well presented. The way statistic facts are visualized within the article is interactive, adequately (almost perfectly) inserted. It’s a smooth read and very well structured, informative article. ...

The symphony hall smells expensive on Feb 14. As ushers barely got the time to nudge the couples chugging off champaigns and sit down, the valentines day night concert began with Joel Thomson’s To See the Sky. The title of the work comes from my favorite line in Cécile McLorin Salvant’s “Thunderclouds,” my favorite song on her album Ghost Songs: “Sometimes you have to gaze into a well to see the sky.” That line gave me so much hope when I heard it. It’s an encouragement toward introspection—she’s saying, Just gaze inward. The well might be your community, the loved ones around you, or your own soul. But the line also acknowledges that there are moments when life gets so hard that you can’t even bother to look up. I’m so prone to melancholy, and I struggle with anxiety and depression. Sometimes I live in that place. ...

Lyric put up a goofy, lighthearted, modern production of Così fan tutte right before Valentine’s Day—doubling as the college night event. Up on the top balcony, we had three flutists sitting together. It was fun (and a little too noisy, as coined by my viola friend). (Lyric is doing Salome exactly on V-day. Nothing more romantic than a woman who, to put it in modern terms, gets swiped left on by a man and responds by having him executed and head on a silver platter) ...

One of my course’s selective paper referee report writing assignment. I like this paper so, here’s the referee report I wrote (lighted edited) which comes with a crisp summarization that I find in times can be quite useful This is a beautifully written, intellectually clean paper. It uses traditional OR methods and is free of fancy deep learning. Bertsimas is a titan of the field. The paper is published in Management Science at an interesting timing of 2020. ...

I Am confused. More than baffled — Don’t know What — was going on — Ariana Emily – No Prisoner Be is a song cycle composed by Kevin Puts based on poems by Emily Dickinson. CSO’s 25/26 season resident artist Joyce DiDonato, who is also the OG artist thet premiered this work, performed the work Feb 12 on Chicago Symphony Center. The stage design and lighting is really fancy ...

I like this model. It’s cute. Unrealistic, but cute. Environment: Intermediate sector. A unit measure of firms $i \in [0,1]$. Firm $i$ produces differentiated variety $Y_i$ with linear technology: $$ Y_i = A_i L_i $$ We assume $A_i\equiv A$ for now. Final sector. A competitive firm aggregates varieties via CES: $$ Y = \left(\int_0^1 Y_i^{\frac{\sigma-1}{\sigma}}, di\right)^{\frac{\sigma}{\sigma-1}}, \qquad \sigma > 1. $$ Consumer. Representative agent with preferences: $$ U = \frac{C^{1-\gamma}}{1-\gamma} - \frac{L^{1+\varphi}}{1+\varphi}. $$ ...

Alchemist 101: don’t create gold. Define what you created as gold. Motivation: find model to predict economic facts Kaldor facts —capital-output ratio and factor shares are roughly constant over time. Kuznets facts — the sectoral composition of employment and consumption shifts systematically: Agriculture (A) down, Manufacturing (M) stable, while Services (S) goes up. Can a single neoclassical growth model deliver both sets of facts simultaneously? Yes, if we throw in the cauldron a non-homothetic preferences (Engel’s law). ...

All models are wrong, but some are useful. — George E. P. Box And, some model would have particularly peculiar assumptions that makes them easy and handy. Motivation The neoclassical growth model was designed to explain several facts observed in developed economies over long periods (the “Kaldor facts” from data from the U.S. (1900-2000)): Output per capita grows at roughly constant rate Capital-output, investment-output, and consumption-output ratios are roughly constant Interest rates are roughly constant Factor shares (capital vs labor income) are roughly constant Uzawa’s Theorem Consider $(K_t, L_t, C_t, Y_t)_t$ governed by: $$ \begin{align*} &\dot K_t = Y_t - \delta K_t - C_t && \text{ accounting formula}\cr & Y(t) = \tilde F(K(t), L(t), \tilde X(t)) && \text{CRS in $(K, L)$ production func.} \end{align*} $$ Assume constant growth rate respectively in production, capital, labor and consumption: $$ \frac{\dot Y}Y = g_Y,\frac{\dot K}K = g_K, \frac{\dot C}C = g_C, \frac{\dot L}L = n. $$ Then, the above conditions (CRS + constant growth) implies ...

Images for Orchestra L. 122 and La Mer. Chicago audience are warm, welcoming. We give a lot of standing ovations: Salonen conducts CSO for Debussy’s La mer. De ja vu: NY Phil opens Shanghai Summer Music Festival with French Impressionism Works See the post here Fun facts: Debussy, Turner, and Impressionism We also know that Debussy greatly admired Turner’s work [the English painter]. His richly atmospheric seascapes recorded the daily weather, the time of day, and even the most fleeting effects of wind and light in ways utterly new to painting, and they spoke directly to Debussy. (In 1902, when Debussy went to London, where he saw a number of Turner’s paintings, he enjoyed the trip but hated actually crossing the channel.) The name Debussy finally gave to the first section of La mer, From Dawn to Noon on the Sea, might easily be that of a painting by Turner made sixty years earlier, for the two shared not only a love of subject but also of long, specific, evocative titles. ...

Motivation Baumol (1967): Differential productivity growth across sectors drives “uneven growth” and structural transformation. As sectors experience different rates of technological progress, this causes relative prices to change and labor to reallocate. Question: Can this supply-side mechanism generate structural change while maintaining balanced growth (Kaldor facts)? Model Household utility: $$ \begin{align*} & \int_0^\infty \exp(-\rho t) \frac{c(t)^{1-\theta} - 1}{1-\theta} dt\cr &s.t. \ \dot K(t) = r(t)K(t) - w(t)\bar L -\sum_{i \in \lbrace A, M, S\rbrace}p^iC^i(t) \ \cr & \text{where, }c(t) = \left(\sum_{i \in {A,S,M}} \eta^i C^i(t)^{(\sigma-1)/\sigma}\right)^{\sigma/(\sigma-1)}. \end{align*} $$ Note that $\sigma$ represents elasticity of substitution (constant across sectors) ...