  A large software system is often composed of many inter-related programs of
different sizes. Using the public Eclipse dataset, we replicate our previous
study on the distribution of program sizes. Our results confirm that the
program sizes follow the lognormal distribution. We also investigate the
implications of the program size distribution on size estimation and quality
predication. We find that the nature of size distribution can be used to
estimate the size of a large Java system. We also find that a small percentage
of largest programs account for a large percentage of defects, and the number
of defects across programs follows the Weibull distribution when the programs
are ranked by their sizes. Our results show that the distribution of program
sizes is an important property for understanding large and complex software
systems.
