What is SLOPE function in Excel?
SLOPE function is one of Statistical functions in Microsoft Excel that returns the slope of the linear regression line through data points in known_y’s and known_x’s. The slope is the vertical distance divided by the horizontal distance between any two points on the line, which is the rate of change along the regression line.
Syntax of SLOPE function
The SLOPE function syntax has the following arguments:
- Known_y’s: An array or cell range of numeric dependent data points.
- Known_x’s: The set of independent data points.
Explanation of SLOPE function
- The arguments must be either numbers or names, arrays, or references that contain numbers.
- If an array or reference argument contains text, logical values, or empty cells, those values are ignored; however, cells with the value zero are included.
- If known_y’s and known_x’s are empty or have a different number of data points, SLOPE returns the #N/A error value.
- The equation for the slope of the regression line is:where x and y are the sample means AVERAGE(known_x’s) and AVERAGE(known_y’s).
- The underlying algorithm used in the SLOPE and INTERCEPT functions is different than the underlying algorithm used in the LINEST function. The difference between these algorithms can lead to different results when data is undetermined and collinear. For example, if the data points of the known_y’s argument are 0 and the data points of the known_x’s argument are 1:
- SLOPE and INTERCEPT return a #DIV/0! error. The SLOPE and INTERCEPT algorithm is designed to look for one and only one answer, and in this case there can be more than one answer.
- LINEST returns a value of 0. The LINEST algorithm is designed to return reasonable results for collinear data, and in this case at least one answer can be found.
Example of SLOPE function
Steps to follow:
1. Open a new Excel worksheet.
2. Copy data in the following table below and paste it in cell A1
Note: For formulas to show results, select them, press F2 key on your keyboard and then press Enter.
You can adjust the column widths to see all the data, if need be.
|Known y||Known x|
|=SLOPE(A3:A9,B3:B9)||Slope of the linear regression line through the data points in A3:A9 and B3:B9.||0.305556|