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e. In physics, the fine-structure constant, also known as the Sommerfeld constant, commonly denoted by α (the Greek letter alpha), is a fundamental physical constant which quantifies the strength of the electromagnetic interaction between elementary charged particles. It is a dimensionless quantity, independent of the system of units used ...
p. -value. In null-hypothesis significance testing, the -value[note 1] is the probability of obtaining test results at least as extreme as the result actually observed, under the assumption that the null hypothesis is correct. [2][3] A very small p -value means that such an extreme observed outcome would be very unlikely under the null hypothesis.
Cronbach's alpha. Cronbach's alpha (Cronbach's ), also known as tau-equivalent reliability ( ) or coefficient alpha (coefficient ), is a reliability coefficient and a measure of the internal consistency of tests and measures. [1][2][3] It was named after the American psychologist Lee Cronbach. Numerous studies warn against using Cronbach's ...
Then alpha diversity can be calculated in two different ways that give the same result. The first approach is to calculate a weighted generalized mean of the within-subunit species proportional abundances, and then take the inverse of this mean. The second approach is to calculate the species diversity for each subunit separately, and then take ...
Thermal diffusivity. In heat transfer analysis, thermal diffusivity is the thermal conductivity divided by density and specific heat capacity at constant pressure. [1] It is a measure of the rate of heat transfer inside a material. It has units of m 2 /s. Thermal diffusivity is usually denoted by lowercase alpha (α), but a, h, κ (kappa), [2 ...
In computer graphics, alpha compositing or alpha blending is the process of combining one image with a background to create the appearance of partial or full transparency. [1] It is often useful to render picture elements (pixels) in separate passes or layers and then combine the resulting 2D images into a single, final image called the composite.
Fisher's method combines extreme value probabilities from each test, commonly known as " p -values ", into one test statistic (X2) using the formula. where pi is the p -value for the ith hypothesis test. When the p -values tend to be small, the test statistic X2 will be large, which suggests that the null hypotheses are not true for every test.
Krippendorff's alpha coefficient, [1] named after academic Klaus Krippendorff, is a statistical measure of the agreement achieved when coding a set of units of analysis.. Since the 1970s, alpha has been used in content analysis where textual units are categorized by trained readers, in counseling and survey research where experts code open-ended interview data into analyzable terms, in ...