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  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    This is the smallest value for which we care about observing a difference. Now, for (1) to reject H 0 with a probability of at least 1 − β when H a is true (i.e. a power of 1 − β), and (2) reject H 0 with probability α when H 0 is true, the following is necessary: If z α is the upper α percentage point of the standard normal ...

  3. Matrix population models - Wikipedia

    en.wikipedia.org/wiki/Matrix_population_models

    Matrix population models are a specific type of population model that uses matrix algebra. Population models are used in population ecology to model the dynamics of wildlife or human populations. Matrix algebra, in turn, is simply a form of algebraic shorthand for summarizing a larger number of often repetitious and tedious algebraic computations.

  4. Boltzmann distribution - Wikipedia

    en.wikipedia.org/wiki/Boltzmann_distribution

    Boltzmann's distribution is an exponential distribution. Boltzmann factor ⁠ ⁠ (vertical axis) as a function of temperature T for several energy differences ε i − ε j.. In statistical mechanics and mathematics, a Boltzmann distribution (also called Gibbs distribution [1]) is a probability distribution or probability measure that gives the probability that a system will be in a certain ...

  5. Gompertz function - Wikipedia

    en.wikipedia.org/wiki/Gompertz_function

    The function also adheres to the sigmoid function, which is the most widely accepted convention of generally detailing a population's growth. Moreover, the function makes use of initial growth rate, which is commonly seen in populations of bacterial and cancer cells, which undergo the log phase and grow rapidly in numbers. Despite its ...

  6. Relative growth rate - Wikipedia

    en.wikipedia.org/wiki/Relative_growth_rate

    For example, since 1 hour is 3 twenty-minute intervals, the population in one hour is () =. The hourly growth factor is 8, which means that for every 1 at the beginning of the hour, there are 8 by the end. Indeed, = ⁡ (⁡ ()) =

  7. Log-normal distribution - Wikipedia

    en.wikipedia.org/wiki/Log-normal_distribution

    City sizes (population) satisfy Gibrat's Law. [87] The growth process of city sizes is proportionate and invariant with respect to size. From the central limit theorem therefore, the log of city size is normally distributed. The number of sexual partners appears to be best described by a log-normal distribution. [88]

  8. Malthusian growth model - Wikipedia

    en.wikipedia.org/wiki/Malthusian_growth_model

    P 0 = P(0) is the initial population size, r = the population growth rate, which Ronald Fisher called the Malthusian parameter of population growth in The Genetical Theory of Natural Selection, [2] and Alfred J. Lotka called the intrinsic rate of increase, [3] [4] t = time. The model can also be written in the form of a differential equation:

  9. Population model - Wikipedia

    en.wikipedia.org/wiki/Population_model

    One of the most basic and milestone models of population growth was the logistic model of population growth formulated by Pierre François Verhulst in 1838. The logistic model takes the shape of a sigmoid curve and describes the growth of a population as exponential, followed by a decrease in growth, and bound by a carrying capacity due to ...