Youyang Gu

Data Scientist

One Year Later

February 26th, 2021

After almost a year since I started, I will be making the last daily update on Sunday, March 7, in concurrence with the conclusion of our main data source, the COVID Tracking Project. There are several reasons for this decision, which I will explain in this post.

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A Dose of Optimism

December 17th, 2020

2020 has seen no lack of depressive outlooks, finger pointing, and pessimistic expectations. We've gotten so used to the negativity that we sometimes forget to look on the positive side. From the resiliency of our frontline health care workers to the movement to fight systemic discrimination, 2020 has also seen no lack of heroes. I want to share three positive things that I have personally experienced this year.

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November 18th, 2020

After a one-month hiatus, I have decided to relaunch For this new project, I try to estimate the number of true infections in every US state and county. This is a nowcasting model (what has happened/is happening) rather than a forecasting model (what will happen).

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Six Months Later

September 28th, 2020

It's been six months since I made my first COVID-19 projections. What started as a small side project became a months long endeavor. 180 days and 180 forecasts later, the pandemic shows no signs of abating as we head towards winter. When I started, there were only a handful of existing models, and very few of them were accurate. Now, there are over 30 models on the CDC Forecasting page. A lot of great progress has been made in the modeling space over the past six months, and I hope others will get to better know these other models in the months to come. After much consideration, I have come to the difficult decision to not extend my projections beyond November 1, 2020. I plan to make the last forecast update to on Monday, October 5. This was undoubtedly a tough choice for me, and I hope to convey my thoughts in this post...

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