A Handful Of Cities Are Driving 2016’s Rise In Murders

Overview

In 2016, there was preliminary evidence that showed that the number of murders for 2016 rose by over 10 percent by October of that year. It rose by 10.8 percent prior to that year, which was a large increase. This data was collected prior to the FBI releasing the official data and came from multiple sources for large cities where the population is greater that 250,000. It is important to note that the murders for the year of 2016 do not account for the entire year. The link to the article can be found here.

URL <- "https://raw.githubusercontent.com/fivethirtyeight/data/master/murder_2016/murder_2016_prelim.csv"
murders <- read.csv(URL)

## preview of variables
str(murders) 
## 'data.frame':    79 obs. of  7 variables:
##  $ city         : chr  "Chicago" "Orlando" "Memphis" "Phoenix" ...
##  $ state        : chr  "Illinois" "Florida" "Tennessee" "Arizona" ...
##  $ X2015_murders: int  378 19 114 72 90 78 52 95 191 17 ...
##  $ X2016_murders: int  536 73 158 111 125 111 79 118 212 34 ...
##  $ change       : int  158 54 44 39 35 33 27 23 21 17 ...
##  $ source       : chr  "https://portal.chicagopolice.org/portal/page/portal/ClearPath/News/Crime%20Statistics" "OPD " "MPD" "PPD " ...
##  $ as_of        : chr  "10/2/2016" "9/22/2016" "9/11/2016" "8/31/2016" ...
## removing variables
murders <- subset(murders, select = -c(source, as_of))

## renaming variables
murders <- rename(murders,c("murders2015" = "X2015_murders", "murders2016" = "X2016_murders"))

## changing the change variable to reflect a percent in change
murders$change <- ifelse(murders$murders2015 == 0, round(murders$change  * 100, 2), 
                         round(murders$change / murders$murders2015 * 100, 2))


## Top 10 cities with the largest change in percent
head(murders[order(-murders$change), ], 10)
##          city      state murders2015 murders2016 change
## 21    Lincoln   Nebraska           0           9 900.00
## 15  Arlington      Texas           4          17 325.00
## 2     Orlando    Florida          19          73 284.21
## 43  Henderson     Nevada           1           3 200.00
## 36      Plano      Texas           2           5 150.00
## 13     Austin      Texas          13          28 115.38
## 10 Fort Wayne    Indiana          17          34 100.00
## 19  Santa Ana California          10          20 100.00
## 26     Mobile    Alabama           6          12 100.00
## 38     Toledo       Ohio           5           8  60.00
## Top 10 cities with the largest amount of murders
head(murders[order(-murders$murders2016), ], 10)
##            city        state murders2015 murders2016 change
## 1       Chicago     Illinois         378         536  41.80
## 75     New York     New York         266         252  -5.26
## 78    Baltimore     Maryland         249         230  -7.63
## 29      Detroit     Michigan         216         221   2.31
## 31 Philadelphia Pennsylvania         209         213   1.91
## 9       Houston        Texas         191         212  10.99
## 63  Los Angeles   California         209         205  -1.91
## 3       Memphis    Tennessee         114         158  38.60
## 58    St. Louis     Missouri         136         133  -2.21
## 55  New Orleans    Louisiana         130         127  -2.31
(sum(murders$murders2016) - sum(murders$murders2015)) / sum(murders$murders2015) * 100
## [1] 10.4685
## Subsetting further to view where more murders than 50 murders occured
mdf <- subset(murders, murders2016 >= 50)

## Top 10 cities with the largest change in percent in mdf
head(mdf[order(-mdf$change), ], 10)
##           city     state murders2015 murders2016 change
## 2      Orlando   Florida          19          73 284.21
## 4      Phoenix   Arizona          72         111  54.17
## 7   Louisville  Kentucky          52          79  51.92
## 6  San Antonio     Texas          78         111  42.31
## 1      Chicago  Illinois         378         536  41.80
## 5    Las Vegas    Nevada          90         125  38.89
## 3      Memphis Tennessee         114         158  38.60
## 11     Atlanta   Georgia          68          85  25.00
## 8       Dallas     Texas          95         118  24.21
## 20       Tulsa  Oklahoma          43          52  20.93
(sum(mdf$murders2016) - sum(mdf$murders2015)) / sum(mdf$murders2015) * 100
## [1] 11.763

Findings and Recommendations

One recommendation would be to recollect the data in order to reflect the number of murders that happened in total for the year of 2016. There are some cities that more than doubled their murder rates, however, it can be beneficial to look at how the cities with the larger amounts of murders contributed to the yearly murder statistic. Overall, the data does seem to contribute to the author’s claim that amount of murders increase by over ten percent. It is also interesting to see that the cities that had more murders, contributed to the increased rate.