If your only goal is to measure the ability to code, then doing a whiteboard interview isn't the best way to do that IMO.
But what about positions where you will be expected to give presentations, do pair-programming, or mentor junior developers? I think whiteboard interviews can be a measure of your ability to take technical concepts and illustrate/explain them clearly to a team.
I used to really hate whiteboards, but as I grew into positions that required more leadership, I realized that I personally needed to develop better presentation skills. If a potential employer were to test me on that, a whiteboard test wouldn't seem unreasonable to me.
So I have mixed feelings on this. Not every hire needs to be capable of being a teacher or delivering a solid keynote speech.. some positions would be best filled by someone with those skills.
If you want to measure giving a public presentation....have them give a public presentation.
If you want to measure their ability to pair program ... pair program with them.
If you want to measure their ability to mentor ... have them teach you something they know.
I want to know how you do X, and measuring X is easy, so please do Y as a proxy is never a good approach.
I have never, in my 25+ year career, ever had to whiteboard a problem, where the other person knows the answer (that is laughable - I've given correct answers and been told they are wrong), I don't, and there are hundreds of thousands of dollars at stake. It just has nothing to do with the job or on the job performance.
If you're whiteboarding with a simple pass/fail mentality, I'd say you're doing it wrong. A good whiteboarding exercise lets you see how a candidate explores a problem. Do they ask insightful questions? How do they break a problem down? Do they bluff when faced with something they don't know?
These are behavioral attributes that are important - much more important than a simple binary test.
Finding out how someone reacts to being told they are wrong when they know that they are right is a totally valid interview technique.
Furthermore, I think past basic fizzbuzz questions, complex interview questions are good, but someone failing to get an objectively correct solution to an objectively difficult problem is just one signal among many. The goal of asking the questions should be to gather lots of other signals about how you approach writing software, not to pronounce you right or wrong.
I had an interviewer tell me that I was wrong that DNS ran over UDP. Not sure if the interviewer was trying to run some psychological test or if he was just wrong.
I was polite and stayed until the end. It was through a headhunter, so I decided to be polite. I knew that was a no-go interview after 1 minute, when I saw that everyone working there was Indian.
Excellent answer Roger. Whiteboard is not a silver bullet. It really depends on what the interview really trying to asses and use a better tool to do that, I would personally prefer to write code in a developer environment (IDE etc) as that is the most natural place for me to write quality code.
White-boarding is good for high level design and architecture but not for actual code.
You're right, I've never whiteboarded a problem where the other person knows the answer. A thousand times have I sat down in front of a whiteboard with coworkers looking to solve a problem. That's how I interview too.
But what about positions where you will be expected to give presentations, do pair-programming, or mentor junior developers? I think whiteboard interviews can be a measure of your ability to take technical concepts and illustrate/explain them clearly to a team.
I used to really hate whiteboards, but as I grew into positions that required more leadership, I realized that I personally needed to develop better presentation skills. If a potential employer were to test me on that, a whiteboard test wouldn't seem unreasonable to me.
So I have mixed feelings on this. Not every hire needs to be capable of being a teacher or delivering a solid keynote speech.. some positions would be best filled by someone with those skills.