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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 | + | *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>. | + | *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>. | + | *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>. | + | *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. |