Pafnuty Lvovich Chebyshev (Пафнутий Львович Чебышёв) (1821-1894) was a Russian mathematician. His name is also transliterated as Tchebycheff or Tschebyscheff.
He is known for his work in the field of probability and statistics. Chebyshev's inequality says that the probability that a random variable is more than a standard deviations away from its mean is no more than 1/a2. If μ is the mean (or expected value) and σ is the standard deviation, then we can state the relation as:
for any positive real number a
. Chebyshev's inequality is used to prove the weak law of large numbers
and the Bertrand-Chebyshev theorem
The Chebyshev polynomials are named in his honor.
In analog electronics there exists a filter family named "Chebyshev filters".