Dog Bite risk in NYC

Charts & Graphs, Visualization


Dog is always one of the most popular pets in American families. They are loyal, affectionate and bring lots of joy to their master. However, a dog can be dangerous without proper training could result in destructive behaviors. Nearly five million people in the US are bitten by dogs each year. The most common victims are children, most of whom are bitten by family pets. Due to a large number of bite records and complexity of the dog breed, I decided to narrow down to NYC and found the top 10 most aggressive dog breeds report. Some facts were very interesting.


The data is between 2015 and 2017 provides by the Department of Health and Mental Hygiene on the NYC OpenData. The metadata includes UniqueID(Unique dog bite case identifier), DateOfBite, Species, Breed, Age, Gender, and SpayNeuter. Since data is about the dog bite, obviously the species will be a dog and it is unnecessary to include it. I also did not choose the gender because there is a large number of the unknown in the dataset and the data could be inaccurate. Therefore, I only selected the uniqueID, DataofBite, Breed, and SpayNeuter to understand the information of the dog bite. Tableau Public was used to create graphs and charts and data cleansing. It is a free interactive data visualization software.

I was very curious to check if the breed with the most attack records in the dataset matched with the report. I also wanted to see where and when people will mostly get bitten in NYC and whether being spayed or unspayed will increase or decrease the records. However, there are over 20 types of breeds in the dataset. In order to clean the breed data, it was sorted to a group of top 10 most aggressive dog breeds based on a report, which were Pit Bull, Chihuahua, Rottweiler, Husky, Dachshund, Chow Chow, Doberman, Russell Terrier, and Dalmatian, the rest of the breeds was sorted to others and was hidden from the graph.

To show the breed with the most attack records, a rank bar chart was used and sorted from highest to lowest, which could easily show the difference and comparison with big data.

For the boroughs, I used treemaps to display hierarchical borough from the highest attacked records to the lowest. People will be able to see the hierarchy as well as the size of the data. Blue color with different shades was also used to display the hierarchy.

To compare the spayed and unspayed data, I used a pie chart to highlight the difference. I decided to use blue as spayed and orange as unspayed. The reason I did it because the blue usually provides calm and positive emotion, the orange since it’s close to red which makes people associate with a sign of danger, warning, and other negative emotions. The contrast between blue and orange is high so the users are able to spot the difference immediately. After having a small UX survey in the class, I noticed people did not know anything about spaying and I added the caption under the chart to help them understand it.

To show the timeline of the dog bite, a line graph is used to display the changing of the bite records of the months. The blue and orange color was also used on this graph. The orange was used for the peak period.


Pit Bull and Chihuahua are the most aggressive breeds

The website report is somewhat accurate. In the report, it says the dachshund is the second most aggressive breed on the report but the data displays Pitbull and Chihuahua are the most aggressive breeds. Pitbull had 810 records while Chihuahua had 453.

Queens has the most biting records

Queens has the most bite records(2520) and Manhattan(2354) is next. Basically from 2015 to 2017, an average of two people was bitten by dogs per day in Queens. Although Queens has the most records, it doesn’t mean people will mostly get bitten there. The cause of the accident can be regional, due to the size of the borough and Queens is by far the largest of the five boroughs.

A spayed dog has a lower chance of biting

The records of a dog biting after spaying(2991) are only one-third of an unspayed dog(7289). It shows that a spayed dog is less aggressive than an unspayed dog. The family who owns a puppy should consider spaying their dog for the dog’s health also to lower the possibility of destructive behaviors.

Summer is the peak period of a dog biting

The orange color shows the dog bite starts records increasing from May till September. There are many reasons for this. Summer is the mating time of dogs. At the same time, because of the hot weather, there are more people on the street and dogs are more likely taken out of the street than other seasons.


The data really got my attention and made me want to dig more information about it. It is one of the most interesting data since I have never seen anyone got bitten by a dog in NYC for 10 years. If I revise this report again, I would love to replace the treemap with an NYC map with color shades so the users will quickly understand the data and see the land size of each borough. I was also struggling with placing the month on the last chart. Few of the months were hidden because of the length and I had to display it vertically to show the whole content. I would love to browse more information about it online to make it more readable.

In addition, I would not say my data is 100% accurate since I didn’t include the other breeds. I would love to compare with anther same data to increase the accuracy. Since my data does not match with the online report, it makes me realize I always need to be suspicious of the reality of the data since people can easily manipulate it. I would say now it is important to have multiple data to make sure the thesis/theory is reliable.