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  2. 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:

  3. Leslie matrix - Wikipedia

    en.wikipedia.org/wiki/Leslie_matrix

    The Leslie matrix is a discrete, age-structured model of population growth that is very popular in population ecology named after Patrick H. Leslie. [1] [2] The Leslie matrix (also called the Leslie model) is one of the most well-known ways to describe the growth of populations (and their projected age distribution), in which a population is closed to migration, growing in an unlimited ...

  4. Malthusianism - Wikipedia

    en.wikipedia.org/wiki/Malthusianism

    Thomas Robert Malthus, after whom Malthusianism is named. Malthusianism is a theory that population growth is potentially exponential, according to the Malthusian growth model, while the growth of the food supply or other resources is linear, which eventually reduces living standards to the point of triggering a population decline.

  5. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4]

  6. Population dynamics - Wikipedia

    en.wikipedia.org/wiki/Population_dynamics

    The rate at which a population increases in size if there are no density-dependent forces regulating the population is known as the intrinsic rate of increase.It is = where the derivative / is the rate of increase of the population, N is the population size, and r is the intrinsic rate of increase.

  7. Population growth - Wikipedia

    en.wikipedia.org/wiki/Population_growth

    Population growth is the increase in the number of people in a population or dispersed group. The global population has grown from 1 billion in 1800 to 8.2 billion in 2025. [ 3 ] Actual global human population growth amounts to around 70 million annually, or 0.85% per year.

  8. Population momentum - Wikipedia

    en.wikipedia.org/wiki/Population_momentum

    The initial population has grown from 700 to 1,200 even though fertility dropped from four to replacement (two) at the end of the third generation. Population momentum carried the population to higher levels over the next two generations. When China first introduced the one-child policy, population growth continued regardless. Even though the ...

  9. Ricker model - Wikipedia

    en.wikipedia.org/wiki/Ricker_model

    Bifurcation diagram of the Ricker model with carrying capacity of 1000. The Ricker model, named after Bill Ricker, is a classic discrete population model which gives the expected number N t+1 (or density) of individuals in generation t + 1 as a function of the number of individuals in the previous generation, [1]