enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Population density - Wikipedia

    en.wikipedia.org/wiki/Population_density

    This population cartogram of the European Union (2007–2012) uses areas and colors to represent population. Living population density by country. Although the arithmetic density is the most common way of measuring population density, several other methods have been developed to provide alternative measures of population density over a specific ...

  3. Number density - Wikipedia

    en.wikipedia.org/wiki/Number_density

    The number density (symbol: n or ρ N) is an intensive quantity used to describe the degree of concentration of countable objects (particles, molecules, phonons, cells, galaxies, etc.) in physical space: three-dimensional volumetric number density, two-dimensional areal number density, or one-dimensional linear number density. Population ...

  4. Probability density function - Wikipedia

    en.wikipedia.org/wiki/Probability_density_function

    In probability theory, a probability density function (PDF), density function, or density of an absolutely continuous random variable, is a function whose value at any given sample (or point) in the sample space (the set of possible values taken by the random variable) can be interpreted as providing a relative likelihood that the value of the ...

  5. Density estimation - Wikipedia

    en.wikipedia.org/wiki/Density_Estimation

    In statistics, probability density estimation or simply density estimation is the construction of an estimate, based on observed data, of an unobservable underlying probability density function. The unobservable density function is thought of as the density according to which a large population is distributed; the data are usually thought of as ...

  6. 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]

  7. Normal distribution - Wikipedia

    en.wikipedia.org/wiki/Normal_distribution

    In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable.The general form of its probability density function is [2] [3] = ().

  8. Urban density - Wikipedia

    en.wikipedia.org/wiki/Urban_density

    Population-weighted density - a density metric which measures the density at which the average person lives. It is determined by calculating the standard density of each census tract, assigning each a weight equal to its share of the total population, and then adding the segments. [11] Residential density - the number of dwelling units in any ...

  9. Probability distribution - Wikipedia

    en.wikipedia.org/wiki/Probability_distribution

    Figure 1: The left graph shows a probability density function. The right graph shows the cumulative distribution function. The value at a in the cumulative distribution equals the area under the probability density curve up to the point a. Absolutely continuous probability distributions can be described in several ways.