Assignment 1 ETC1010 - 5510
New South Wales Crime Incidents Report
Your name
Friday, March 12 2021
Instructions to Students
This assignment is designed to simulate a scenario in which you are taking over someone’s existing work and
continuing with it to draw some further insights.
This is a real world dataset taken from the New South Wales Bureau of Crime Statistics and Research.
The data can be found here at https://www.bocsar.nsw.gov.au/Documents/Datasets/SuburbData.zip.
Specifically, the data file called “SuburbData2019csv” located in your data folder inside the RStudio project
will be used for this assignment.
You have just joined a consulting company as a data scientist. To give you some experience and guidance,
you are performing a quick summary of the data while answering a number questions that the chief business
analytics leader has. This is not a formal report, but rather something you are giving to your manager that
describes the data with some interesting insights.
Please make sure you read the hints throughout the assignment to help guide you on the tasks.
The points allocated for each of the elements in the assignment are marked next to the code for each question.
Marking + Grades
• This assignment will be worth 10% of your total grade, and is marked out of 116 marks total. Due
on: Friday 26 March.
For this assignment, you will need to upload the following into Moodle:
- Your Rmd file,
- The rendered html file, and
- The PDF rendered file.
How to find help from R functions?
Remember, you can look up the help file for functions by typing: ?function_name. For example, ?mean.
Feel free to google questions you have about how to do other kinds of plots, and post on the “Assignment
Discussion Forum” any questions you have about the assignment.
How to complete this assignment?
To complete the assignment, you will need to fill in the blanks with appropriate function names, arguments,
or other names. These sections are marked with ___. At a minimum, your assignment should be able
to be “knitted” using the Knit button for your Rmarkdown document.
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If you want to look at what the assignment looks like in progress with some of the R codes remaining invalid
in the R code chunks, remember that you can set the R chunk options to eval = FALSE like so:
```{r this-chunk-will-not-run, eval = FALSE} `r''`
ggplot()
```
If you use eval = FALSE or cache = TRUE, please remember to ensure that you have set to eval
= TRUE when you submit the assignment, to ensure all your R codes run.
There are a few tricky bits that might require you to look back into your previous R code chunks (that is
intentionally done for you to understand how things work within an Rmd file!)
You will be completing this assignment INDIVIDUALLY.
Due Date
This assignment is due in by close of business (5pm) on Friday, 26 March 2021. You will submit the assignment
via Moodle. Please make sure you add your name on the YAML part of this Rmd file.
Treatment
You work as a data scientist in the well-named consulting company, “Consulting for You”.
It’s your second day at the company, and you’re taken to your desk. Your boss says to you:
We have a data set with the crime statistics in New South Wales for the past years!
We’ve got a meeting coming up soon to get insights about the crime in NSW. We want you to
tell us about this data set and what we can do with it.
You’re in with the new hires of data scientists here. We’d like you to take a look at the data and
tell me what the spreadsheet tells us. I’ve written some questions on the report for you to answer.
Most importantly, can you get this to me by 5pm, Friday, 26 March 2021.
Please read below and answer all the questions (ensure that you can knit the file to produce an
html file and a PDF file to hand them in to me via Moodle):
Load all the libraries that you need here
library(tidyverse)
Reading and preparing data
crime_dat <- read_csv("data/SuburbData2019.csv")
# I am selecting here only a portion of the data
# to reduce computation times.
crime_data <-crime_dat %>%
select(-c(`Jan 1995`:`Jan 2010`)) %>%
dplyr::filter(Suburb %in% c("Chifley",
"Redfern",
"Clare",
"Paddington",
"Redfern",
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"Zetland",
"Claymore",
"Congo",
"Yenda",
"Young",
"Yarra",
"Woodcroft",
"Woodhill",
"Warri",
"Waterloo",
"Randwick"))
Question 1: Display the first 10 rows of the data set
Hint: Check ?head in your R console
head(---, 10) # 1pt
Question 2: How many variables and observations do we have?
Hint: Look for help ?dim in your R console and remember that variables are in columns and observations in
rows. dim() returns the number of rows and the number of columns in the data set (in that order)
dim(---) # 1pt
The number of variables are dim(crime_data)--- (1pt) and the number of rows are dim(crime_data)---
(1pt)
Question 3: What are the names of the first 20 variables in this
data set?
names(---)[1:20] #1pt
Question 4: Rename the variable of “Offence category” to “Of-
fence_category” and show the names of the first 4 variables in the
data set
crime <- crime_data %>%
rename(--- = `Offence category`) # 1pt
names(crime)[---] #1pt
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Question 5: Change the “crime” data (“SuburbData2019csv”) into
long format so that all the years are grouped together into a variable
called “year” and the corresponding incidents count into a variable
called “incidents”
crime_long <- crime %>%
pivot_longer(cols = ---:---, # 2pt
names_to = "---", # 1pt
values_to = "---") # 1pt
head(---) # 1pt
Question 6: Separate the column “year” into two columns with
names “Month” and “Year”. Display the first 3 lines of the data
set to show the updated data set
crime_long_new <- crime_long %>%
separate(col = ---, # 1pt
into = c("---", "---"), " " ) # 2pt
head(---) # 1pt
Question 7: If you look at the data crime_long_new, you will
notice that the variable of “Year” is coded as character. In this
section, we are going to convert the variable of “Year” to a numeric
variable
crime_long_new %>%
mutate(Year = as.numeric(---)) # 1pt
head(---) # 1pt
Question 8: Display the years in the data set. How many years are
included in this data set?
Remember that you can learn more about what these functions by typing: ?unique or ?length
into the R console.
unique(crime_long_new$---) # 1pt
# length tell us the length or longitude of a variable or a vector
length(unique(---)) #1pt
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Question 9: How many different suburbs are there in the data set?
length(unique(---)) # 1pt
n_distinct(---) # 1pt
Question 10: How many incidents do we have per “Offence_category”
in total for 2019?
crime_long_new %>%
dplyr::filter(Year == "---") %>% # 1pt
count(--- , wt = incidents) # 1pt
Question 11: Which is the “Offence_category” with highest num-
ber of incidents in 2019?
crime_long_new %>%
dplyr::filter(Year == "---") %>% # 1pt
count(---, wt = ---, sort = ---) # 1pt
Question 12: How many offences are there in each Subcategory of
the “Offence_category” of Homicide?
crime_long_new %>%
dplyr::filter(Offence_category == "---") %>% # 1pt
group_by(---) %>% # 1pt
summarise(Number_of_incidents = sum(---)) # 1pt
Question 13: Select the suburb called “Paddington” and calculate
the number of incidents for “Offence_category” of “Drug offences”
then calculate the total number of incidents for each Subcategory.
Finally, show a table arranged by “Number_of_ incidents” (high
to low)
Paddington <- crime_long_new %>%
dplyr::filter( ---== "---", # 2pt
Offence_category == "---") %>% #1pt
group_by(---) %>% # 1pt
summarise(Number_of_incidents = sum(---)) %>% # 1pt
arrange(---) # 1pt
head(---) # 1pt
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Question 14: Let’s have a look at the changes over time for “Pos-
session and/or use of cannabis” in the suburb of Paddington
To answer this question, we need to first filter the “Suburb” and the “Subcategory”. Then, group incident by
year and finally sum the number of incidents for each year
Paddington_cannabis <- crime_long_new %>%
dplyr::filter( Suburb == ---, # 1pt
Subcategory == ---) %>% # 1pt
group_by(Year) %>% # 1pt
summarise(Number_of_incidents = --- %>% #1pt
mutate(Year = as.numeric(---)) # 1pt
head(---,3) # 1pt
Question 15: Create a line plot to display the trend of the incidents
that you calculated for Paddington
On the x-axis you should have “Year” and on the y-axis you should display “Number_of_incidents”
ggplot(Paddington_cannabis, aes( x = ---, y = ---)) + # 2pt
geom_line() # 1pt
Question 16: Create the same plot as in Question 15 but now in-
clude also the suburb called “Randwick” (you will see two trends in
the same plot). Make sure that the variable of “Suburb” is defined
as a factor
both_cannabis <- crime_long_new %>%
dplyr::filter(Suburb %in% c("---", ---), # 1pt
Subcategory == "---") %>% # 1pt
group_by(Year, Suburb) %>% # 1pt
summarise(Number_of_incidents = --- %>% # 1pt
mutate(Year = as.numeric(---), # 1pt
Suburb = as.factor(---)) # 1pt
ggplot(both_cannabis, aes( x = ---, # 1pt
y = ---, # 1pt
color = ---)) + # 1pt
geom_line() # 1pt
Question 17: Let’s now look at the total number of crime incidents
in NSW and create a plot to visualize the trend
crime_long_new %>%
dplyr::select( ---, # 1pt
---) %>% # 1pt
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---(Year) %>% # 1pt
summarise(Number_of_incidents = --- %>% # 1pt
mutate(Year = as.numeric(---)) %>% # 1pt
ggplot(aes(x = ---, y = --- )) + # 1pt
geom_line() # 1pt
Question 18: Now, let’s change the background color of the plot to
white using the theme_bw()
crime_long_new %>%
dplyr::select(---, # 1pt
---) %>% # 1pt
group_by(---) %>% # 1pt
summarise(--- = ---) %>% # 1pt
mutate(Year = as.numeric(---)) %>% # 1pt
ggplot(aes(x = ---, y = --- )) + # 1pt
geom_line() + # 1pt
theme_--- # 1pt
Question 19: Let’s change the line color to green and replace it
with a dotted line
crime_long_new %>%
dplyr::select(---, # 1pt
---) %>% # 1pt
group_---(Year) %>% # 1pt
---(--- = sum(---)) %>% # 1pt
mutate(--- = as.numeric(---)) %>% # 1pt
ggplot(aes(x = ---, y = --- )) + # 1pt
geom_line(linetype = ---, color =---) # 1pt
Question 20: Now, let’s look at the total number of crime incidents
for the suburbs of Redfern, Coogee, and Zetland by creating a bar
plot where we have the incidents per suburb by year next to each
other
comparison_data<- crime_long_new %>%
dplyr::select(---, # 1pt
---, # 1pt
---) %>% # 1pt
dplyr::filter( --- %in% c("Redfern", "Coogee", "Zetland")) %>% # 1pt
group_by(---, ---) %>% # 1pt
summarise(Number_of_incidents = ---(---)) # 1pt
ggplot(comparison_data, aes(x = ---, # 1pt
--- = ---, # 1pt
fill = ---)) + # 1pt
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geom_bar(--- = "identity", # 1pt
position = "---") + # 1pt
---(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) # 1pt
Question 21: Change the x and y-axis labels to “Years” and "
Incidents", respectively, for the figure in Question 20 and use the
black and white theme
ggplot(comparison_data, aes(x = ---, # 1pt
y = ---, # 1pt
fill = ---)) + # 1pt
geom_bar(--- = "identity", # 1pt
--- = "dodge") + # 1pt
---_bw() + # 1pt
---(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) + # 1pt
xlab("---") + # 1pt
ylab("---") # 1pt
Question 22: Add the following title to the figure constructed in
Question 21: “Number of criminal incidents”
ggplot(comparison_data, aes(x = ---, # 1pt
y = ---, # 1pt
fill = ---)) + # 1pt
geom_bar(--- = "---", # 1pt
position = "---") + # 1pt
theme_---() + # 1pt
---(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) + # 1pt
---("Years") + # 1pt
---("Incidents") + # 1pt
ggtitle("---") # 1pt
Question 23: By using “facet_wrap”, create a line plot to show the
trends for “Number_of_incidents” for each of the three suburbs
ggplot(comparison_data, aes(--- = Year, # 1pt
--- = Number_of_incidents, # 1pt
--- =Suburb)) + # 1pt
geom_---() + # 1pt
facet_wrap(~---) + # 1pt
---() + # 1pt
---(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) # 1pt
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Question 24: Transform the data set named comparison_data into
a wide format where the suburbs of Coogee, Redfern, and Zetland
are displayed as columns
comparison_data %>%
pivot_wider(id_cols = ---, # 1pt
names_from = ---, # 1pt
values_from = ---) # 1pt
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