Analysis of Mass Shootings and Gun Ownership in the United States

Posted on Nov 10, 2022



It should come to no one's shock that there is a gun violence crisis in the United States right now. As of July, there had been 372 mass shooting in 2022 and the US had not gone a single week without a mass shooting.

My analysis project focused on two research questions:
1. Is there a relationship between gun ownership and gun violence in the United States?
2. What parts of the United States have been most afflicted with mass shootings?

To begin this analysis, I began my work with two datasets. First, historical data of mass shootings from 1920 to 2022 with a full breakdown of casualties, year, and description. The second data set looked at registered firearms by State in 2019 and 2021.


Mass Shootings

Before we begin - we should define what is a mass shooting. These are incidents of public firearm violence, in which the shooter claims at least four victims. As we can see from the graph below, there has been a 41,975% increase in mass shootings over the last 100 years.

There has been a steady increase in casualties from 1920 to 2000 in the United States.Β From 2000 to present we see a sharp increase, with casualties rising by 1,051% from 2000 to 2010.Β Since 2010, we have seen aΒ 60% increase in gun violence in the U.S.


Overall, individuals were 100 times more likely to be injured versus killed in a mass shooting.Β On average, there are four people injured for every person killed.

The data showed that the cities with the highest number of mass shooting casualties are Chicago, Paradise (NV), and Philadelphia. While the States with the highest number of casualties are California, Illinois, and Texas.


Gun Ownership


It is staggering to see the number of registered firearms. In 2019, there was a total of 5,201,947; that number increased to 7,511,303 in 2021.

An important thing to remember when seeing these numbers is that these reflect legal and registered firearms. There are only six states which require the registeration of firearms under law. Thus, the majority of guns fly under the radar and remain unregistered. There is an estimated 393 million total firearms in the United States.


Overall, southern states have more federal registered firearms compared to the Northeast. Only two states showed a decrease in registered firearms from 2019 to 2021: Connecticut (-9.13%) and Illinois (-1.18%). The three states with the highest increase are South Dakota (206%), North Dakota (133.3%), and Mississippi (127.3%).



Overall, there appears to be a relationship between number of firearms and risk of gun violence by state.

The states with a higher number of registered firearms generally have a higher number of gun violence casualties.

The Federal Assault Weapons Ban lasted from 1994 to 2004.

After its expiration in 2004, we can see a dramatic increase into present day. Mass shootings were 70% less likely to occur during the ban compared to present day.Β Some of the deadliest mass shootings in US history have occurred in our lifetime.

Future Work

  • Accessing earlier records for firearm ownership
  • Additional data on shooter demographics (age, gender, race, income, etc.)
  • Further breakdown mass shooting incidents, looking at political party of state leadership


About Author

Natalie Zadrozna

Welcome to my blog! Today I am an innovative and scientifically rigorous data scientist. But before going into data science, I worked in databases and archives for 10 years. I have been responsible for collection databases and using...
View all posts by Natalie Zadrozna >

Related Articles

Leave a Comment

No comments found.

View Posts by Categories

Our Recent Popular Posts

View Posts by Tags

#python #trainwithnycdsa 2019 2020 Revenue 3-points agriculture air quality airbnb airline alcohol Alex Baransky algorithm alumni Alumni Interview Alumni Reviews Alumni Spotlight alumni story Alumnus ames dataset ames housing dataset apartment rent API Application artist aws bank loans beautiful soup Best Bootcamp Best Data Science 2019 Best Data Science Bootcamp Best Data Science Bootcamp 2020 Best Ranked Big Data Book Launch Book-Signing bootcamp Bootcamp Alumni Bootcamp Prep boston safety Bundles cake recipe California Cancer Research capstone car price Career Career Day citibike classic cars classpass clustering Coding Course Demo Course Report covid 19 credit credit card crime frequency crops D3.js data data analysis Data Analyst data analytics data for tripadvisor reviews data science Data Science Academy Data Science Bootcamp Data science jobs Data Science Reviews Data Scientist Data Scientist Jobs data visualization database Deep Learning Demo Day Discount disney dplyr drug data e-commerce economy employee employee burnout employer networking environment feature engineering Finance Financial Data Science fitness studio Flask flight delay gbm Get Hired ggplot2 googleVis H20 Hadoop hallmark holiday movie happiness healthcare frauds higgs boson Hiring hiring partner events Hiring Partners hotels housing housing data housing predictions housing price hy-vee Income Industry Experts Injuries Instructor Blog Instructor Interview insurance italki Job Job Placement Jobs Jon Krohn JP Morgan Chase Kaggle Kickstarter las vegas airport lasso regression Lead Data Scienctist Lead Data Scientist leaflet league linear regression Logistic Regression machine learning Maps market matplotlib Medical Research Meet the team meetup methal health miami beach movie music Napoli NBA netflix Networking neural network Neural networks New Courses NHL nlp NYC NYC Data Science nyc data science academy NYC Open Data nyc property NYCDSA NYCDSA Alumni Online Online Bootcamp Online Training Open Data painter pandas Part-time performance phoenix pollutants Portfolio Development precision measurement prediction Prework Programming public safety PwC python Python Data Analysis python machine learning python scrapy python web scraping python webscraping Python Workshop R R Data Analysis R language R Programming R Shiny r studio R Visualization R Workshop R-bloggers random forest Ranking recommendation recommendation system regression Remote remote data science bootcamp Scrapy scrapy visualization seaborn seafood type Selenium sentiment analysis sentiment classification Shiny Shiny Dashboard Spark Special Special Summer Sports statistics streaming Student Interview Student Showcase SVM Switchup Tableau teachers team team performance TensorFlow Testimonial tf-idf Top Data Science Bootcamp Top manufacturing companies Transfers tweets twitter videos visualization wallstreet wallstreetbets web scraping Weekend Course What to expect whiskey whiskeyadvocate wildfire word cloud word2vec XGBoost yelp youtube trending ZORI