Who devised the formula for calculating sample size in a survey?

The formula for calculating sample size in a survey has been developed and refined by various statisticians over time, with significant contributions from figures such as Jerzy Neyman and Ronald A. Fisher. Neyman's work in the 1930s laid the foundation for modern sample size determination, emphasizing the importance of margin of error and confidence levels. The basic formula considers population size, desired confidence level, margin of error, and variability within the population. Today, many variations of the formula exist, tailored to specific research needs and contexts.