Why do you use pseudorandom numbers in simulation?

Answer 1

Generation of random numbers is not a simple process. In order for a number to be truly random it must be uniformly distributed (each random number in the interval of random numbers has equal chance of being selected), efficiently generated (the random numbers hsould not degenerate into constant values or recycle too frequently) and absent of patterns. Computers can generate random numbers using a mathematical process that artificially creates psuedorandom numbers more efficiently than true random numbers can be generated in a process akin to spinning the roulette wheel.

Answer 2

There are two main reasons. One is that most sequences of random numbers are generated using algorithms. These are tested to ensure that the numbers appear to be random but, because they are generated systematically, they are pseudo random numbers and not truly random.

It is sometimes necessary to re-run a simulation - reproducibility is an important requirement of scientific research. This would clearly be impossible if truly random numbers were used. However, given the necessary "seed or seeds", the same sequence can be reproduced.