y^x | y to the power of x (also seen as y**x or y^{x}) |
^Key | Ctrl + another Key |
/ | divided by (see calculator for operator precedence) |
* | multiplied by (see calculator for operator precedence) |
abs(x), |x| | absolute value of x without regard to sign |
alpha, α | significance level of a hypothesis test (also type I error rate). 1-a is the level of the confidence interval |
ANOVA | analysis of variance |
beta, β | type II error rate (1-power) |
CI | confidence interval, see confidence intervals |
df | degrees of freedom |
e | base of natural logarithms (2.718281...) |
k! | factorial , in simplest terms factorial of k is the product of all integers from 1 to k, with 0! defined as 1, a fuller definition relates factorial to the gamma function as gamma (k+1) which enables the calculation of fractional factorials |
ln(x) | natural (base e) logarithm of x, the natural logarithm of x is the value of y such that x is equal to the e constant raised to the power of y, remember that ln(1) = 0, ln(0) = minus infinity and ln(a/b)=ln(a)-ln(b), see also transformations |
MS | mean square |
μ | mean of a population - see also |
n | sample size (population sized is usually referred to as N) |
P | probability of the data (or more extreme data) arising by chance, see P values |
p | proportion of a sample with a given characteristic |
q hat, the hat symbol above the q means "estimate of" | |
r | Pearson's product moment correlation coefficient |
SD | standard deviation (of a sample, ) - a measure of variability around the mean - Greek lower case sigma (σ) is used for population standard deviation. |
SE | standard error (of sample mean, ) - a measure of uncertainty of the estimate of a statistic (e.g. sample mean) and used to derive confidence intervals for the population value of the statistic |
sqr(x) | square root of x, or |
sum of all (1 to n) x values | |
product of all (1 to n) x values (x_{1} * x_{2} * x_{3} etc.) | |
VAR | variance (of the mean, ), greek σ² for populations and s² for samples |
vs. | versus |
x | individual value from a population or sample |
x bar (bar symbol above the x denotes mean) is a sample mean (arithmetic mean, ), see also μ | |
z, Φ | standardized normal deviate (from standard normal distribution) |
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