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*It is fits a straight line through the set of <math> n </math> points in such a way that makes vertical distances between the points of the data set and the fitted line as small as possible.
 
*It is fits a straight line through the set of <math> n </math> points in such a way that makes vertical distances between the points of the data set and the fitted line as small as possible.
 
*Regression methods nearly to the simple ordinary least squares also exist.  
 
*Regression methods nearly to the simple ordinary least squares also exist.  
*i.e.,The Least Squares method relies on taking partial derivatives with respect to the slope  
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*i.e.,The Least Squares method relies on taking partial derivatives with respect to the slope and intercept which provides a solvable pair of equations called normal equations.
and intercept which provides a solvable pair of equations called normal equations.
   
*Suppose there are <math> n </math> data points  <math> {y_{i}, x_{i}}</math>, where i = 1, 2, …, n.
 
*Suppose there are <math> n </math> data points  <math> {y_{i}, x_{i}}</math>, where i = 1, 2, …, n.
*To find the equation of the regression line:<math> a=bar{y}-b.bar{x}</math>.
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*To find the equation of the regression line:<math> a=\bar{y}-b.\bar{x}</math>.
 
*This equation will give a "best" fit for the data points.  
 
*This equation will give a "best" fit for the data points.  
 
*The "best" means least-squares method. Here b is the slope.
 
*The "best" means least-squares method. Here b is the slope.
*The slope is calculated by:<math> b=\frac{\sum_{i=1}^{n} {(x_{i}-\bar{x})(y_{i}-\bar{y})}} {\sum_{i=1}^{n}{(x_{i}-bar{x})}^2}</math>.  
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*The slope is calculated by:<math> b=\frac{\sum_{i=1}^{n} {(x_{i}-\bar{x})(y_{i}-\bar{y})}} {\sum_{i=1}^{n}{(x_{i}-\bar{x})}^2}</math>.  
*In this formula<math> bar{x}</math> and<math> bar{y}</math> are the sample means  AVERAGE of <math> x</math>  and <math> y </math>.  
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*In this formula<math> \bar{x}</math> and<math> \bar{y}</math> are the sample means  AVERAGE of <math> x</math>  and <math> y </math>.  
 
*In <math>INTERCEPT(y,x)</math> , the arguments can be numbers, names, arrays, or references that contain numbers.
 
*In <math>INTERCEPT(y,x)</math> , the arguments can be numbers, names, arrays, or references that contain numbers.
 
* The arrays  values are  disregarded when it is contains text, logical values or empty cells.  
 
* The arrays  values are  disregarded when it is contains text, logical values or empty cells.  
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