The Square Root Law , also known as the “Root Rule,” is a principle or formula used to predict how performance will change as the size of a group or team effort increases. They often apply this concept to project management , software development, and team performance analysis.
Square Root Law bases efficiency on quantity of people or effort. Other team members do not have a linear, but decreasing effect. The improvement grows with the square root of the number of members.
Mathematically, we can express it as:
Total performance = Constant value * square root(of number of people or effort)
A team with 4 members has a performance of 100 units. Adding 4 more members may not double the performance. Instead, an increase of about 2x is expected since the square root of 8 (original 4 members + added 4) is about 2.83.
The Square Root Law shows that adding more team members has diminishing marginal benefit. Therefore, it is important to carefully consider when and how many people we add to projects or teams. We will thus achieve optimal results and minimize losses in efficiency .
