Random-Number Guessing and the First Digit Phenomenon

To what extent do individuals “absorb” the empirical regularities of their environment and reflect them in behavior? A widely-accepted empirical observation called the First Digit Phenomenon or Benford's Law says that in collections of miscellaneous tables of data (such as physical constants, almanacs, newspaper articles, etc.), the first significant digit is much more likely to be a low number than a high number. In this study, an analysis of the frequencies of the first and second digits of “random” six-digit numbers guessed by people suggests that people's responses share some of the properties of Benford's Law: first digit 1 occurs much more frequently than expected; first digit 8 or 9 occurs much less frequently; and the second digits are much more uniformly distributed than the first.