## Avondale Estates is having a backlash

Martin Luther King feared fully expected that there would be a backlash as basic human rights for African Americans expanded. There were historic precedents for this such as the reversal of post-Civil War Reconstruction-era freedoms during the last decades of the 19th century and the rise of segregationist laws throughout the southern US during the 1950s. Ta-Nahesi Coates speaks eloquently on the last incarnation of this in his Atlantic piece The First White President.

I am witnessing the evolution of this fourth backlash wave play out where I live, just east of Atlanta. Yesterday, my family and I witnessed the incident which is the featured image of this post. A White police officer handcuffs, and humiliates a young Black man about 15 feet from us through the window of a shop were we frequently have a relaxed brunch. The shop, I should mention is owned by a Black woman, also a resident of Avondale Estates. I should have stood with my young Brother and recorded the incident — sadly I know that life will give me other opportunities. To witness is a powerful comfort and statement. The young man showed calm and grace, as many of us have learned to do in such situations (I’ve been there).

Avondale Estates, a little east of Atlanta until recently had de-facto housing segregation through special real estate covenants. The history of housing segregation in Georgia, and the Atlanta area is both fascinating and frightening. If you zoom in on the Avondale Estates area, you’ll notice interesting racial disparities. There’s more information in this 50-year look back at the fair housing act.

Avondale Estates and the small towns to it’s north and east have been notorious for the disproportionate amount of revenue garnered from African Americans being stopped for minor traffic violations.

Georgia cities — especially Stone Mountain and Clarkston lead the nation in the fining of Black people

I wish we knew more, but like it’s voting transparency, information on racism in policing in Georgia is hard to come by.

Although one of my close friends (also African American) purchased a home in Avondale Estates in the ’90s, anecdotally (just from informal conversation), the number racialized policing and other incidents around exclusion have continued to grow.

I’ll detail one particular issue I’ve encountered. In Avondale, several times when walking while Black, my family and I have encountered on several occasions the question “Do you live around here?” Word of caution and advice for any (non-Black) person with the bad home training to ask this question. The 14th amendment of the Constitution of the United States is generally understood as guaranteeing access to the public roads to any US citizen, “green card” holder, or basically any human being regardless of what they look like. Dear White People, it’s not your militia/Klan duty to keep American or Avondale Estates or any other space in this country White. There’s my peculiar rant.

What can done? A few suggestions:

• Check out the hash tag #StopRacialProfilingAvondaleEstatesGA
• When you see these incidents going down, use your phone and record.
• Start demanding accountability from your police officers, city and county representatives.

Let’s end the police state together.

## You should record technical talks!

A few days ago I attended the talk “Sparsity, oracles and inference in high-dimensional statistics” by Sara van der Geer who is visiting Georgia Tech. The talk is described here.

But I didn’t record the talk! I had a working iPhone! I only have an after thought photo of the white board that remained after the lecture

Just focus on lambda!

Phones are ubiquitous and there’s nothing like a short clip that can distill some of the essence of an idea, a lecture. Maybe it’s all those “No recording devices, please!” announcements at concerts, or that my videography skills are in need of serious help.

PSA: If you think that someone is bring across some important knowledge, record it — give them their attribution, don’t steal their stuff — but you are sharing knowledge with the world!

So what was the talk about? If you do machine learning, the idea of regularization is probably familiar. L1 regularization a.k.a Least Absolute Shrinkage and Selection Operator ak.a. lasso in particular assigns a penalty on the absolute value of the predictor weights. It’s an technique that reduces the tendency to overfit to the training data. There’s a whole book on it called Statistical Learning with Sparsity that you can download for free!

The amazing thing about lasso is that it also drives the less extraneous parameters close to zero: it can reduce the number of parameters you need in your model, or it results in a model that is more sparse (that is, just remove the close-to-zero parameters from the model). This can make the model faster to compute.

The main things I picked up were that there are some bounds on the error for lasso regularization that can be expressed in terms of the number of parameters and the number of observations you have in your training set. The error should be within a constant of $\sqrt{s_{o} log(p)/n}$ , where I believe that $s_{0}$ is your guess about the smallest non-sparse weight. You also get a similar expression for a good starting value for the penalty $\lambda >> \sqrt{ log(p)/n}$. The p is the number of parameters in your model, and n the number of observations you are training with. Scikit-learn or your favorite machine learning library probably comes with the lasso, but it doesn’t look like the bound results are baked in.

She introduced something called the compatibility constant that’s discussed further in a couple of papers [Belloni, et. a. 2014, Dalalyan 2017]. She also discussed how lasso behaves when you assume that you have noisy observations. The final lecture is September 6th at Georgia Tech on applications to inference.

Wouldn’t it have been better if I’d just recorded it though??

## The science of data science

The Foundations of Data Science Boot Camp given last week (August 27 –  31) at the Simons Institute in Berkeley explored how pure mathematics and theoretical computer science are providing actionable insights that the working data scientist can use — or at least ponder.

I found the talk below by Ravi Kannan useful in pointing out how dimensionality reduction techniques like SVD can be used to set clustering up for success. When dealing with immense data sets, this can be the difference between useful or garbage clusters.

I also thought that David P. Woodruff‘s lecture on a dimensionality reduction technique called sketching was impressive for its clarity. As a data scientist or analysis, you’re often in a dilemma when your Impala cluster runs out of memory for that critical model build — you may just have to sample from that terabyte pile of web pages. It is good to know that you have some math magic behind you when the time comes.

Santosh Vempala thinks the seminar was a better value than Netflix. I’m not sure about that, but those were some good lectures.

My colleague Boris Gorelik continues to deliver the insights of a data science sage. You should study carefully his recent EuroSciPy 2018 talk “Data visualization: from default to efficient”

Then check out his notes on how to continuously improve a talk.

## Gayatri interviews Yuyi Morales at Decatur Book Festival

My partner Dr Gayatri Sethi is interviewing celebrated writer and illustrator Yuyi Morales today at the Decatur Book Festival today, Saturday, September 1 from 1:00 to 1:30. They’ll be discussing Morales’ new book Dreamers.

Isn’t it time you talked to your children about what is going on at the border? Dreamers talks about Morales’s own 1994 journey from Xalapa, Mexico to the US. with her child. It is such a beautifully illustrated book, and a profound story with so many layers.

## AI at HBCUs Fall 2018

If you teach/study computer science at a Historically Black College or University, or know of someone who does, please check out and pass along the site https://charlescearl.github.io/ai-hbcu/.

I put it up a year or so ago to document the work being done at those institutions to increase the impact and participation of the African Diaspora in shaping the way that AI technologies are developed and used. As this recent report by the ACLU points out, yes algorithmic racism is still a thing.

If you know of important initiatives, interesting classes, or discussions going on at HBCUs around this issue, please feel empowered to check out the repository https://github.com/charlescearl/ai-hbcu and send a pull request. Or drop a comment below.

I was encouraged to see that the Neural Information Processing conference (one of the most attended AI conferences) is taking steps towards inclusion. They keep promising to change their name.

## Havana: whimsical artchitecture

Cuba has left us with a lot to think about. Still coming to terms with its lessons on race, identity, the bounty of being out of one’s place of comfort, and most importantly those on human dignity and kindness.

While I make sense of those lessions, I’ll share some photos from Vedado, Trinidad, and points in between that testify to the whimsical, surprising beauty of this country and its people.