Jersey City Salaries

I've been spending some time looking at the open data available for Jersey City via its "open data initiative." There's an active (and great) meetup: Code for JC that you should join if you're similarily interested.

Annoyingly, much of the data the city has is trapped in image-only-pdfs (cannot even copy/paste text out of the pdf). This led me to start: imagepdftotxt. Saddly I've stalled on that project because the remaining work is writing a GUI for easily use/consumption (I use Qt) and the effort is a nightmare. To regain some sanity I decided to have some fun looking at some of the already digestable data.

Salaries are a fun place to start because everyone likes snooping on how much people make, and public employee salaries are... well... public! You can download the raw here.

So... how much do people actually make working for Jersey City (you)? Anywhere from: $1 to $187,230 USD a year is the short answer (median: $61000, mean: $70765). The long answer is interesting. Here is a histogram of the salaries.

My first question was: What's the deal with no one making ~90k a year?! Looking at city-data.com the median household income in JC is $57,166, but ~90k a year appears to be normal income for a downtown household, so it's pretty interesting that a city employee simply wouldn't be able to afford the living downtown or would easily be able to afford it, but nothing inbetween. For external reference I compared against Chicago's salary distribution (raw data).

That looks regular... much more regular. Why does no one make a mid range salary in JC? Well, there's another piece of data that might help us here; in the JC salary data a hire date is also provided. Calculating the distance from current time we get the lengths of employment.

There's a noticable dip in the middle of employment length. On pure speculation you can imagine a scenario where at a certain point in ones career you'd have to decide if you're going to work in Jersey City forever (and collect a pension) or move on to a higher paid position. A quick google found a number of articles concerning issues in Jersey City's pension and subsequent policy changes. From this news article:

This bill was actually passed January 2014, so it would be interesting to look at employment history immediately approaching the date the bill was passed. Either way, it's no wonder the city, quite sadly, has little mid-level talent.

Since I had the length of employment data, I figured it would be interesting to see what the correlation between length of employment and pay really was. So here are the correlation coeffecients of time-to-salary for the entire city, and by city department

Not so bad! Every department has a positive correlation. The lowest correlation is in the Mayor's Department, where I assume positions are appointed/elected and probably change with each new administration. Is anyone's pay in particular not correlated to their length of employment? Well, here's the scatter-plot of the entire city (categorized by department).

Who is that in the upper left? Why, it's Director of Public Safety James Shea recently (2013) hired from the NYPD. Hopefully his experience justifies his outlier status.

The final question that came to my mind was simply: "What's the best department to work in Jersey City?" The highest paid department, on average, is the Fire Department, where average compensation is $101,229.05 a year. Sadly (or appropriately) it's also the place where compensation is most correlated to length of employment, so maybe it's not the best place for a rising star. So, where can I get paid the most for working the least amount of time? To answer this question I simply generated a ratio of mean salary to mean time worked (by department).

And the best place to work in Jersey City is... by far, the Mayor's Office, where return on time spent is literaly twice that of any other department. The next best place to work actually is the Fire Department, where the outsized average salary dominates the time it takes to get it. Interestingly, however, the Law Department and Recreation Department (of all places) actually have high returns on employement time (very close in to the Fire Department's score). As an aside, the worst place to work in the city is the Tax Assessor's office, where earning potentional is half of just about anywhere else in the city. Below are the respective values for these specific departments.

So there you have it, a cursory look at Jersey City's public employee salaries. Future work could include:

• Comparative analysis with other cities
• Employee by Employee analysis - finding outliers using multiple regression (against their department and the city as whole)
• Historical hiring practices (would require more years of data)

I am doing none of this (at least for now) because I've grown bored of the topic, but I hope you've enjoyed this whirlwind tour of how your money is being spent. I've attached my research source code below for your review/use and I hope people will start looking at this (and other) open data sets.

-A