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y^x 
y to the power of x (also seen as y**x or ) 


^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, a 
significance level of a hypothesis test (also type I error rate). 1a is the level of the confidence interval 


ANOVA 



beta, b 



CI 
confidence interval, see confidence intervals 


df 



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, s = SQR(VAR))  a measure of variability around the mean  Greek lower case sigma (s) 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, equivalent to 


sum of all (1 to n) x values 



product of all (1 to n) x values (x1 * x2 * x3 etc.) 



VAR 
variance (of the mean, ), greek s² 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 m 



Z, N 
standardized normal deviate (from standard normal distribution) 