How to Pass the Data Presentation Part of Interviewing

Photo by Jason Goodman on Unsplash

The dreaded data presentation. This is often the part of the interview process where candidates either shine or dig their own grave.

Some candidates drop out altogether once they find out they need to actually do some analysis and present their findings. You want me to do hours worth of work!? How dare you even ask?

Personally, I think this is the most telling part of the process.

First, you can see how much effort someone is willing to put into finding some interesting patterns in your data.

Second, it proves that a candidate can think creatively and actually do the technical work the role requires them to do every day.

If you’re applying for a data analyst role and the company asks you to use their data to create a presentation, you should be eager to complete it. It’s not every day that you get to see a company’s real data, let alone explore it to answer some interesting problems.

If you are dreading the presentation, maybe the role or company isn’t right for you. As data-people, we jump at any chance to look at real numbers from real users and products.

So, if you’re willing to put in the work and excited about the presentation, here’s a few things you need to make sure you do in order to succeed.

Clean your data.

You’d be surprised how often a candidate doesn’t even mention cleaning the data. As a data science nerd, I’ve learned over and over again how important it is to have clean data. This is super important to me when listening to a candidate’s presentation.

Mention what you did to fix any errors in the datasets you were given. Did you have to cast any data types? Eliminate outliers? Replace any null values? Give a brief overview of the steps you took.

Junk data in equals junk data out. Your analysis is only as accurate as the data you are using to fuel it.

Now you don’t have to go super in-depth here, depending on the position you’re applying for. If you’re applying for a data scientist role, this may be extremely important. However, if you’re applying for a data analyst role, this is something you may just want to touch on briefly.

Go above and beyond.

I’ve been shocked by the number of times candidates have only touched the surface of the datasets we’ve given them. There have been people who have only presented basic counts and averages, expecting us to be impressed.

Counts and averages are expected, not impressive. Make sure you are always going above and beyond what is asked of you. The whole point of these presentations is to show that you are a creative thinker and can execute on your ideas.

Brainstorm interesting hypotheses and use the data to back up whether those hunches were correct or not. We want to see strategic thinking.

During one of my interviews, the candidate only presented for the first five minutes. After five minutes, she was done! She only showed us some basic graphs built using Excel and didn’t even look at an entire dataset that we gave her.

She did the absolute bare minimum. If you can call it that. If your presentation doesn’t take up 75% of the meeting time, it is probably too short.

While quantitative analysis is obviously important, qualitative is also a huge part of your success. You need to mention why you think the numbers are the way they are. Could there be seasonal trends in the data? Maybe there was a back-end issue collecting ratings?

It is not so much about these hypotheses being right as it is about you even thinking about them in the first place. So much of what data analysts do involves experimentation and testing. Prove that you can think in that way.

Show clear visualizations.

Your data visualizations need to be strong and concise if you want to properly communicate your findings. In my opinion, this is the most important part of one’s role as a data analyst.

A large part of your job is visualizing data in a way that business teams, specifically those that aren’t technical, understand. You don’t want these visualizations to be easy to misinterpret.

Here are my top tips for creating strong visualizations:

• Categorize by color.

• Don’t use pie charts.

• Make sure you give every graph a title and axis labels.

• Use the same color scheme for the same dimensions throughout your presentations.

• Simpler is better. Don’t fit more information than is needed.

It can be easy to get caught up in proving all of the cool things you can do with graphs. Cool graphs are impressive! But are they useful? Not really.

Always think in terms of functionality and storytelling over something being unique. Don’t use certain skills just to show them off. This is when visualizations become cluttered and lose their value.

Stay within the time limit.

This one drives me crazy. If the meeting scheduled for your presentation is only 30min long, make sure your presentation is 25min or less. If your presentation if scheduled for an hour, make sure it is only 45min or less.

You should practice giving your presentation multiple times before giving it to those at the company you are interviewing for. Time yourself and make sure you don’t go over these limits.

There is nothing more disrespectful than wasting someone’s time. Your interview is scheduled for a certain period of time for a reason. Respect that and stay within those limits.

One time, I was interviewing a candidate, and his presentation went 10min over the time we had scheduled. And he still wasn’t finished! This showed he didn’t know the data or his work as well as he was trying to let on. And it left me feeling irritated. The person who is interviewing you should always leave the conversation inspired and excited.

Exceeding this time limit shows that you didn’t practice your presentation at all and you don’t respect other people’s time. It is already pretty draining to do data presentation after data presentation as an interviewer. The last thing you want is for someone to exceed the boundaries you put in place.

Leave 5 or 10 minutes at the end for questions from the team. There are always going to be questions, so, again, leaving some time allows you to respect the limits others have put in place.

Conclusion

Remember, the most important thing is that you have fun and show off what you can do! Interviewers want to understand your strategic thinking process and how you execute on your ideas.

You don’t have to go crazy with grand visualizations, just make sure you are thinking in both qualitative and quantitative terms. Make sure your visualizations tell a story and clearly communicate your ideas.

When I interviewed for my current role, I followed all of the tips I listed above. I spent hours after work every single day and on the weekends working on my data presentation. I put in the work and it showed. Interviewers know whether you put a few hours in versus all of your free time.

If you’re really passionate about the company and the role, you will enjoy this process. I firmly believe that success comes naturally when we are excited about the work we are doing.