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  2. On-base percentage - Wikipedia

    en.wikipedia.org/wiki/On-base_percentage

    The statistic was invented in the late 1940s by Brooklyn Dodgers statistician Allan Roth with then-Dodgers general manager Branch Rickey. [3] [4] In 1954, Rickey, who was then the general manager of the Pittsburgh Pirates, was featured in a Life Magazine graphic in which the formula for on-base percentage was shown as the first component of an all-encompassing "offense" equation. [5]

  3. Z-value (temperature) - Wikipedia

    en.wikipedia.org/wiki/Z-value_(temperature)

    The z-value is a measure of the change of the D-value with varying temperature, and is a simplified version of an Arrhenius equation and it is equivalent to z=2.303 RT T ref /E. [2] The z-value of an organism in a particular medium is the temperature change required for the D-value to change by a factor of ten, or put another way, the ...

  4. t-statistic - Wikipedia

    en.wikipedia.org/wiki/T-statistic

    Most frequently, t statistics are used in Student's t-tests, a form of statistical hypothesis testing, and in the computation of certain confidence intervals. The key property of the t statistic is that it is a pivotal quantity – while defined in terms of the sample mean, its sampling distribution does not depend on the population parameters, and thus it can be used regardless of what these ...

  5. Stefan–Boltzmann law - Wikipedia

    en.wikipedia.org/wiki/Stefan–Boltzmann_law

    T ⊕ can then be found: = = = where T ⊙ is the temperature of the Sun, R ⊙ the radius of the Sun, and a 0 is the distance between the Earth and the Sun. This gives an effective temperature of 6 °C on the surface of the Earth, assuming that it perfectly absorbs all emission falling on it and has no atmosphere.

  6. Z-test - Wikipedia

    en.wikipedia.org/wiki/Z-test

    A t-test can be used to account for the uncertainty in the sample variance when the data are exactly normal. Difference between Z-test and t-test: Z-test is used when sample size is large (n>50), or the population variance is known. t-test is used when sample size is small (n<50) and population variance is unknown.

  7. Wilcoxon signed-rank test - Wikipedia

    en.wikipedia.org/wiki/Wilcoxon_signed-rank_test

    For two matched samples, it is a paired difference test like the paired Student's t-test (also known as the "t-test for matched pairs" or "t-test for dependent samples"). The Wilcoxon test is a good alternative to the t-test when the normal distribution of the differences between paired individuals cannot be assumed. Instead, it assumes a ...

  8. Reaction rate constant - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate_constant

    where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here ⁠ ⁠ is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...

  9. Student's t-distribution - Wikipedia

    en.wikipedia.org/wiki/Student's_t-distribution

    For the statistic t, with ν degrees of freedom, A(t | ν) is the probability that t would be less than the observed value if the two means were the same (provided that the smaller mean is subtracted from the larger, so that t ≥ 0). It can be easily calculated from the cumulative distribution function F ν (t) of the t distribution: