Topic: Data Science

I am a data scientist by profession and personality. I love trying to answer a question by finding the right data and pulling the answer out of it. I write about the tools I use to do data science, the methods, and even some of my results. You can find my articles on the subject below:

Black and white photo from around 1920 of men in suits with hats crowded around a car that has driven over a curb and lost its front left wheel.
SWITRS: Pedestrian Safety on Halloween
Halloween can be a dangerous time for pedestrians. In this post, I explore the statistics on pedestrian-vehicle collisions, including when these incidents are most likely to occur.
Black and white photo from 1926 of men and boys crowded around a car that has driven into a lamppost and lost it's front left wheel.
SWITRS: On What Days Do Drivers Hit Pedestrians?
Being a pedestrian is dangerous in a world built for automobiles. In this post explore how pedestrian-involved collisions have trended in time. Take a look!
A line drawing of a mission style home from Architect and Engineer magazine.
Comparing Zillow, Redfin, and Realtor.com Price Estimates in Time
How do various online brokers' home price estimates change in time? I use a recently sold house near my neightborhood to find out. Come check it out!
A line drawing of two houses in San Francisco from Architect and Engineer magazine.
Comparing Zillow and Redfin Price Estimates in Time
How do Zillow and Redfin's home price estimates change in time? I use a recently sold house in my neightborhood to find out. Come check it out!
A line drawing of a two bedroom home done for a 1935 architecture competition.
Comparing Pre- and Post-sale Estimates of the Price of a House
Can Zillow and Redfin predict prices accurately? I look at a house sold in my neighborhood and compare the sale price to the price predicted by Zillow and Redfin before they knew it was for sale.
Painting by Josef Wagner-Höhenberg showing a late 1800s farmer signing a contract at a wooden table while a notary gestures to the two bankers at the other end of the table who have a pile of gold and silver coins in front of them.
Data Science, Compensation, and Asking for Money
Advice about data science salaries and examples from my career of negotiating your offer.
A black and white photo from 1927 of an old USPS truck crashed into a tree at the side of the road.
SWITRS: Differences in Vehicle Collision Rates by Manufacturer During COVID-19
California was put under a stay-at-home order in March, 2020. Toyota drivers stayed home, Ford drivers did not; why?!
A black and white photo of an old car slid up against the curb, its front wheels completely buckled. A crowed stands on the sidewalk looking on.
SWITRS: Increase In Traffic Fatalities After COVID-19 Lock Down
California was put under a stay-at-home order in March, 2020. As expected, traffic volume decreased, but what happened to rate of fatal accidents? They skyrocketed!
A triangular prism breaking white light into its components.
The Data Science Spectrum:
From Analyst to Machine Learning
Data science has left the era of the Unicorn and entered the era of the team, but that means there is now a whole spectrum of data science jobs. Here is what they do.
Gene Kranz sits at a console in the NASA Mission Operations Control Room. He is wearing a single ear headset and flipping a pencil back and forth.
The Data Science Split:
From Unicorns to Teams
When data science started the job covered everything from setting up databases to running experiments to making models. But finding Unicorns was impossible; something had to give.
An overhead photo of a Department of Energy supercomputer showing the ethernet interconnects.
Where to Host Public Datasets?
When I released the SWITRS dataset, I had to find a place to host a 5 Gig dataset. Here is what I learned.
The planet Jupiter as seen by the departing Juno spacecraft.
Jupyter Notebook Templates for Data Science: Plotting Time Series
Jumpstart your time series visualizations with this Jupyter plotting notebook!
The planet Jupiter as seen by the Juno spacecraft.
Jupyter Notebook Templates for Data Science: Plotting
Jumpstart your visualizations with this Jupyter plotting notebook!
A photo of the Library of Congress in 1902.
Jupyter Notebook Templates for Data Science
Jupyter notebooks are great for data exploration; jumpstart your work with this library of useful notebook templates!
A painting of coins on a table by Josef Wagner-Höhenberg.
The Gender Pay Gap in Data Science Salaries
How do the salaries of woman data scientists compare to those of men? This month we explore pay by gender and location.
A painting of coins on a table by Josef Wagner-Höhenberg.
Data Science Salaries
How do data scientists salaries vary by experience and location? Read on to find out!
An 1890s advertisement for Wilhelmina Cycle Co. Ltd. showing a family on bicycles.
SWITRS: On What Days Do Cyclists Crash?
California crash data doesn't just cover cars, it covers bikes too! This time we look at when cyclists crash in California.
A blonde woman adjusts the time on a row of clocks at a store.
SWITRS: Car Crashes After Daylight Saving Time Ends
Day light saving time leaves leads to more traffic collisions, but what about when DST ends? Some researchers have found that it does lead to more crashes, so I take a look using California's SWITRS data.
A set of four blue Fate dice resting on top of a wooden table.
Fate Dice: Statistics Testing Is Hard
A few months ago I tested my Fate dice for biases. Now, I retest the "biased" set and see if it really is unlucky! Unfortunately, things aren't so clear...
An oil painting titled 'Fate', painted in 1920 by Alphonse Mucha. It depicts a woman in a white robe holding an oil lamp.
Fate Dice Intervals
What does a "normal" distribution of rolls from a fair set of Fate dice look like? There are a lot of ways to estimate it. In this post I'll go through four methods.
Three sets of four Fate dice, colored blue, red, and black, resting on top of a wooden table.
Fate Dice Statistics
My friends and I played a Fate RPG for over two years. During that time we rolled a lot of dice and developed a lot of superstitions, but were any of them correct?
An avant-garde painting of a violin by Kuzma Petrov-Vodkin from 1921.
Visualizing Multiple Data Distributions
Need to compare a set of distributions of some variable? Histograms are OK, but try something fancier! Read on to learn about box, strip, swarm, and violin plots!
A man adjusts the central time of the Gare Saint-Lazare in Paris, 1937.
SWITRS: Car Crashes After Daylight Saving Time
Day light saving time leaves us drowsy and cranky at work, but it also leads to an increase in traffic collisions! Find out exactly how many more there are with this analysis!
A black and white photo from 1959 of a policeman in full-leather protective gear. He stands over a motorcycle on side of a street in Stockholm as traffic passes by.
SWITRS: On What Days Do Motorcycles Crash?
Motorcycles riders are a different breed, born to chase excitment! So when do they crash? Using California's SWITRS data I find out! I'll give you a hint: it is not on the way to their 9-5!
A pile of worn bricks covered in dust and chips of other bricks.
Software Testing for Data Science
Much of data science involves writing code; for data cleaning, parsing, and modeling. Software tests can ensure that your code does what you think it does!
A black and white photo of about a dozen men and boys standing around a broken car taken in Washington D.C. in 1923. One of the car's wheels has splintered and the car is tilted over.
SWITRS: On What Days Do People Crash?
What day of the year has the most car crashes? The fewest? Find out as I look at California's crash data! Hint: they're both holidays!
A screenshot of the front page of WhereTo.Photo.
WhereTo.Photo: Using Data Science to Take Great Photos
Where is the best spot to take a photo in San Francisco? Learn how I answered this question with my Insight Data Science project!
A black and white photograph of a child filling in a bar graph on a chalkboard.
Further Double-checking FiveThirtyEight's 2016 Primary Predictions
Is FiveThirtyEight's Polls Plus model biased against any candidate? I continue my double-checking their model by looking at each candidate individually.
A black and white photograph of a child filling in a bar graph on a chalkboard.
Double-checking FiveThirtyEight's 2016 Primary Predictions
How well did FiveThirtyEight do in predicting the primary results? I Double-check FiveThirtyEight's Polls Plus model by comparing its predictions to the outcomes of the 2016 primaries.