How long does it take to write a phd thesis?

In the domain of computerprogramming there is a benchmark available which measures the productivity of an average author. No matter how good somebody is, or which programming language he is using, he will reach only 10 lines of code per day. In the domain of thesis writing there is a similar benchmark available. Here is the question how many hours somebody needs to write a single page in his phd-thesis. The average value is 4 hours per page. That means, if the aim is to create a 150 page long thesis, the average author needs 600 hours.

The interesting aspect is, that we can discuss about this benchmark. Perhaps if it is to demanding and in reality the author will need 8 hours per page. But according to different discussions in the Internet, the number of 4 hours per page is fair to describe the current situation. It predicts quite good, what is possible and what not. Let us make a thought experiment. Somebody needs a 10 page long article for a journal submission. According to our above cited formula he will need 10 pages * 4 hours = 40 hours to write the paper. Is it possible to reduce the effort dramatically? No, like in the example with the programming productivity, it is a fixed value which is surprisingly constant over periods. What is possible is to try to increase the value, for example with a better wordprocessing software which allows faster formatting of a paper. But at the end, the bottleneck is the author himself. His ability to read the given literature, doing experiments and understand a domain is limited.

To make the situation a bit more realistic we can search for any dissertation on the internet. Perhaps the pdf document contains of 150 pages. We can download and read the dissertation in under 5 minutes, but for creating it the author had invested lots of energy. In most cases, a phd thesis was written over 2 years. It is the result of an ongoing research effort, which takes not only weeks but months until it was finished. And this is perhaps the most important reason for the Open Access movement. If a single phd thesis needs many months to write, it is a waste of energy to hide it from the public. The best time-saving advice is to not write any academic paper. That is only possible if paper written in the past are available in the internet, so there is no need to write the same information again.