REGR_SXX
REGR_SXX is an SQL function used in statistical analysis. It calculates the sum of the squares of the differences between the dependent variable's observed values and its mean, allowing further computation of variance or standard deviation.
REGR_SXX(Y, X)
- y: This is the dependent variable in the linear regression model. It is typically a column name indicating the response, or output, variable whose values you seek to explain or predict.
- x: This is the independent variable in the linear regression model. It is typically a column name representing the predictor, or input, variable that explains or predicts the values of the dependent variable Y.
Example
Output
Explanation
In the provided example, REGR_SXX(salary, commission_pct)
computes the covariance of the salary and commission percentage of employees. Covariance is a measure of how much two random variables vary together. It is easy to calculate the covariance between two variables using the REGR_SXX
function in SQL.
REGR_SXX(Y, X)
- y: This is the dependent variable in the regression equation. It is a numeric or a non-null input column in the database from which the function will establish a relationship.
- x: This is the independent variable in the regression equation. It represents a numeric or non-null input column in the database that influences a dependent variable (Y).
Example
Output
Explanation
In the provided example, the REGR_SXX()
function is applied on work_experience
and salary
columns of the Employee
table. This function calculates the sum of squares of differences from the mean for work_experience
(the dependent variable) per unit of salary
(the independent variable). The resultant value, 4.67, indicates the variability of work_experience
per unit of salary
.