Symbol 
Text Equivalent 
Meaning 
Formula 
Link to Glossary (if appropriate) 

a 

Y intercept of least square regression line 
, for line 
Regression: y on x 
b 

Slope of least squares regression line 
for line 
Regression: y on x 

Binomial distribution with parameters n and p 
Discrete probability distribution for the probability of number of successes in n independent random trials under the identical conditions. 
If X follows then, , Where, , r = 0,1,2, …….,n,


c 

Confidence level 


^{n}C_{r} 
ncr 
Combinations (number of combinations of n objects taken r at a time) 
, where 


ncr 
Combinations (number of combinations of n objects taken r at a time) 
, where 


Covariance between X and Y 
Covariance between X & Y 


CV 

Coefficient of variation 


df 

Degree(s) of freedom 


E 

Maximal error tolerance 
for large samples 

E (f(x)) 
Expected value of f(x) 



f 

Frequency 
number of times score. 

F 

Fdistribution variable 
where n_{1} and n_{2} are the corresponding degrees of freedom.

Fdistribution, Hypothesis testing for equality of 2 variances. 
or


Distribution function 
. 

f(x) or


Probability mass function

Depends on the distribution.


H_{0} 
Hnaught 
Null hypothesis 
The null hypothesis is the hypothesis about the population parameter. 

H_{1} 
Hone 
Alternate hypothesis 
An alternate hypothesis is constructed in such a way that it is the one to be accepted when the null hypothesis must be rejected. 

IQR 

Interquartile range 


MS 
MS 
Mean square 


n 

Sample size. 
number of units in a sample. 

N 

Population size 
Number of units in the population. 


npr 
Permutation (number of ways to arrange in order n distinct objects taking them r at a time) 
where 


npr 
Permutation (number of ways to arrange in order n distinct objects taking them r at a time) 
, where 


phat 
Sample proportion 



Probability of A given B 
Conditional probability 



Probability of x 
Probability of x 


pvalue 

The attained level of significance. 
P value is the smallest level of significance for which the observed sample statistic tells us to reject the null hypothesis. 

Q 

Probability of not happening of the event 


Q_{1} 
Qone 
First quartile 
Median of the lower half of the data that is data below median. 

Q_{2} 
Qtwo 
Second quartile Or Median 
Central value of an ordered data. 

Q_{3} 
Qthree 
Third quartile 
Median of the upper half of the data that is data above the median. 

R 

Sample Correlation coefficient 


r^{2} 
rsquare 
Coefficient of determination 


R^{2} 
rsquare 
Multiple correlation coefficient 


S 

Sample standard deviation 
for ungrouped data. for grouped data. 

S^{2} 
Ssquare 
Sample variance 
for ungrouped data. for grouped data. 


se square 
Error variance 


SD 

Sample Standard deviation 
for ungrouped data. for grouped data. 



Bowley’s coefficient of skewness 




Pearson’s coefficient of skewness 




Sum of squares 
for ungrouped data for grouped data 

t 

Student’s t variable 


t_{c} 
t critical 
The critical value for a confidence level c. 
Number such that the area under the t distribution for a given number of degrees of freedom falling between and is equal to c. 

Var(X) 
Variance of X 
Variance of X 


X 

Independent variable or explanatory variable in regression analysis 
Eg. In the study of, yield obtained & the irrigation level, independent variable is, Irrigation level. 


xbar 
Arithmetic mean or Average of X scores. 
for ungrouped data. for grouped data 

y 

Dependent variable or response variable in regression analysis 
Eg. In the study of, yield obtained & the irrigation level, dependent variable is, Yield obtained. 

Z 
Zscore 
Standard normal variable (Normal variable with mean = 0 & SD = 1) 
, where X follows Normal . 


z critical 
The critical value for a confidence level c. 
Number such that the area under the standard normal curve falling between and is equal to c. 