Analyzing Crime in Chicago

Initial Overview
data_science
visualization
Author

Felix

Published

May 1, 2022

Abstract

This report’s intent is to give an initial overview of the recorded incidents of crime in the city of Chicago from 2001 to 2021. The data is provided in a publicly available dataset by the Chicago Police Department. The report is an initial overview about the total numbers of crimes, their types, and development over time. All charts in this report have been created with Apache Superset.

It is the first report in a series that is based on the data of this dataset and its purpose is to lay the groundwork for further analysis.

Table of contents

from IPython.display import Image
from pathlib import Path

Introduction

The following report will give an overview on the development of crime counts in the city of Chicago from 2001 to 2021. This analysis includes includes a broad overview on the total number of crimes in the dataset, their development over time and the distribution of the types of crime. We will also have a look on the trend of recorded number of crimes overall and in detail.

Data

This analysis is based on the reported incidents of crime in the City of Chicago. The dataset starts in the year of 2001 and is updated daily. It only excludes the most recent seven days. The data is provided by the Chicago Police Department itself. This dataset records among others the date and time of the incident, detailed information on the location, the crime type and description, if an arrest was made and if it was a domestic crime.

This dataset is publicly available on the Chicago Data Portal: - https://data.cityofchicago.org/Public-Safety/Crimes-2001-to-Present/ijzp-q8t2

The accuracy, completeness, timeliness or correct sequencing of the provided records is not guaranteed. So comparisons of over time created with it should be taken with a grain of salt. In addition, older records are subject to change.

Analysis

Crime in General

At first let us take a look on the total amount of crimes committed and what their primary types are. From 2001 to 2021 there have been a total of 7.47 million recorded crimes by the Chicago Police Department. Overall these crimes split into 36 different types. The most common crimes are theft, battery, criminal damage and cases involving narcotics. These four types alone amount to 4.5 million of the 7.47 million records overall, which is 61 %.

path = Path.cwd().joinpath('images').joinpath('r#1').joinpath\
    ('01.jpg')
Image(filename=path)

Next, we will investigate the development of the crime count per year. Overall there has been a steady decline in the number of recorded crimes since 2001. In the beginning there we roughly 486,000 counted crimes compared to the 206,000 in 2021. The decline in felonies comes although the population has increased by 2 % from 2010 to 2020. It rose from 2.696 million to 2.746 million according to the united status census bureau[1].

[1] https://www.census.gov/quickfacts/fact/table/chicagocityillinois/POP010210#POP010210

path = Path.cwd().joinpath('images').joinpath('r#1').joinpath\
    ('02.jpg')
Image(filename=path)

Another important distinction to look at is the the percentage of domestic crimes overall. 1.02 million of the total crimes counted were flagged as domestic. This results in a share of 13.66 % of all committed crimes. Further analysis shows that the share per year steadily increases as the absolute number of domestic crimes stagnates. The amount of non-domestic crime continues to decrease since 2001.

path = Path.cwd().joinpath('images').joinpath('r#1').joinpath\
    ('03.jpg')
Image(filename=path)

Conclusion

In general, there was a continuous decrease in the number of recorded crimes since 2001 by 57.6 percent. This comes although the population in Chicago has risen. Despite this decrease took place, in these 20 years domestic crime has been relatively stable and not nearly decreased that much. Hence the non-domestic crime has seen a much larger decline. Theft, Battery and criminal damage have been the three most committed crimes since the beginning. Theft was the most, battery the 2nd and criminal damage the 3rd most recorded type. Crimes involving narcotics have seen the largest decrease. From being the fourth most recorded crime in 2001 to dropping down to the tenth most recorded.

In the following reports we will take a further look at the areas in which crimes are committed and their development over time. And in addition I will take a deep dive into crime types and their development.