# Two Birthday Problem Modifications: Non-Uniform Case

## DOI:

https://doi.org/10.20535/1810-0546.2016.4.76267## Keywords:

Birthday problem, Birthday paradox, Random allocations, Fermi statistic, Uval attack## Abstract

**Background.** The scheme of random allocation of particles in cells is studied both in probability theory and mathematical statistics. In probability theory usual study is concerning limit theorems, in mathematical statistics – construction statistical criteria’s. Birthday problem is one of main questions in this theory.

**Objective.** Two modifications of the birthday problem are considered in the paper. One was formulated in Fermi statistic scheme, another – in non-uniform and independent random allocation scheme. In both cases the objective was to solve a birthday problem.

**Methods.** Standard asymptotical methods were used. At first we needed to prove one limit theorem and to estimate rapidity of convergence in it. Using these results numerical calculation of probabilities from birthday problem was made. Also formulas for the group size from birthday problem were obtained.

**Results.** As a result numerical estimates for birthday problem probability and group size were obtained.

**Conclusion.** For both modifications main asymptotic values coincide, as in the formula for probability calculation, as in the formula for the group size. But second terms from their asymptotic series are already different.

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