Statistics Canon: Statistics and Math Symbols
神掌打通任督二脈‧易筋經以簡馭繁
符號意義:統雄快訣 延伸閱讀 進階議題 警示訊息
統計常用符號與其英語讀法
Pronunciations of Statistical Symbols
Relational Symbols | |||
---|---|---|---|
= | equals is the same as |
≠ | is not equal to is different from |
> | is greater than is more than exceeds is above |
≥ or >= |
is greater than or equal to is at least is not less than |
< | is less than is fewer than is below |
≤ or <= |
is less than or equal to is at most does not exceed is not greater than is no more than |
A < x < B | x is between A and B, exclusive | ||
A ≤ x ≤ B | x is between A and B, inclusive | ||
A ≅ B | A is approximately equal to B |
Here are symbols for various sample statistics and the corresponding population parameters. They are not repeated in the list below.
sample statistic |
population parameter |
description |
---|---|---|
x̅ “x-bar” | μ “mu” or μx |
mean |
M
(TIs say Med) |
(none) | median |
s
(TIs say Sx) |
σ “sigma”
or σx |
standard deviation For variance, apply a squared symbol (s² or σ²). |
r | ρ “rho” | coefficient of linear correlation |
p̂ “p-hat” | p | proportion |
zo to χ²o | (n/a) | calculated test statistic |
μ and σ take subscripts to show what you are taking the mean or standard deviation of. For instance, σx̅ (“sigma sub x-bar”) is the standard deviation of sample means, or standard error of the mean.
Other symbols — Roman letters
- b = y intercept of a line (Some statistics books use b0.)
- CLT = Central Limit Theorem
- d = difference between paired data
- df or ν “nu” = degrees of freedom in a Student’s t or χ² distribution
- E = margin of error, a/k/a maximum error of the estimate
- f = frequency
- f/n = relative frequency
- Ho = null hypothesis
- H1 or Ha = alternative hypothesis
- IQR = interquartile range, Q3−Q1
- m = slope of a line (The TI-83 uses a and some statistics books use b1.)
- n = sample size, number of data points, or number of trials in a probability experiment
- p = probability value. In binomial probability
distributions p is the probability of “success” (however defined) on any
one trial and
q = 1−p is the probability of “failure” (the only other
possibility) on any one trial.
In hypothesis testing, p is the calculated p-value, the probability that rejecting the null hypothesis would be a wrong decision. In tests of population proportions, p stands for population proportion and p̂ for sample proportion (see table above). You have to rely on context to know what “p” means. - P(A) = the probability of event A. (Sometimes P′(A) is used to distinguish the experimental probability of event A from the theoretical probability.)
- P(AC) = probability of not-A, the probability that A does not happen
- P80 or P80 = 80th percentile (Pk or Pk = k-th percentile)
- Q1 or Q1 = first quartile (Q3 or Q3 = third quartile)
- R² = coefficient of determination
- SEM = standard error of the mean (symbol is σx̅)
- SEP = standard error of the proportion (symbol is σp̂)
- x = a variable or a data value (raw score). As a column heading, x means a series of data values.
- ŷ “y-hat” = predicted average y value for a given x, found by using the regression equation
- z = standard score or z-score. Using the
individual score x, the mean μ, and the standard deviation σ, the formula is
Using a sample mean x̅ and comparing it to the distribution of sample means, the formula is - z(area) or zarea = the z-score, such that that much of the area under the normal curve lies to the right of that z. This is not a multiplication!
Greek letters (see also the table above):
- α “alpha” = significance level in hypothesis test, or acceptable probability of a Type I error (probability you can live with); 1−α = confidence level
- β “beta” = in a hypothesis test, the acceptable probability of a Type II error; 1−β is called the power of the test
- σx̅ “sigma-sub-x-bar” = standard error of the mean (abbreviated SEM)
- σp̂ “sigma-sub-p-prime” = standard error of the proportion (abbreviated SEP)
- ∑ “sigma” = summation. (This is upper-case sigma. Lower-case sigma means standard deviation of a population; see the table above.) Be careful with the order of operations, such as ∑x² versus (∑x)².
- χ² “chi-squared” = distribution for multinomial experiments and contingency tables
數學常用符號與其英語讀法
Pronunciations of Mathematical Symbols
引用自 UEfAP (Using English for Academic Purposes: A Guide for Students in Higher Education)。
[RwdPurpleWoo/Literature/!DataAnalysis/Pronunciation of mathematical symbols.html]來源與參考連結 Source and Related Links
http://www.tc3.edu/instruct/sbrown/ti83/normcalc.htm
http://cnx.org/content/m16302/latest/
http://www.statistics.com/uploads/statsymbols.pdf
http://www.rapidtables.com/math/symbols/Statistical_Symbols.htm
http://stattrek.com/statistics/notation.aspx
http://www.uefap.com/speaking/symbols/symbols.htm