Correlation is called the mutual dependence of two random variables (more often - two groups of values), in which a change in one of them leads to a change in the other. The correlation coefficient shows how likely the change in the second quantity is when the values of the first change, i.e. the degree of its dependence. The easiest way to calculate this value is to use the corresponding function built into the Microsoft Office Excel spreadsheet editor.
Necessary
Microsoft Office Excel spreadsheet editor
Instructions
Step 1
Start Excel and open a document containing the data groups for which you want to calculate the correlation coefficient. If such a document has not yet been created, then enter the data into an empty table - the spreadsheet editor creates it automatically when the program starts. Enter each of the groups of values, the correlation between which you are interested in, in a separate column. These do not have to be adjacent columns, you are free to design the table in the most convenient way - add additional columns with explanations to the data, column headings, total cells with total or average values, etc. You can even arrange data not vertically (in columns), but horizontally (in rows). The only requirement that must be observed is that the cells with the data of each group must be placed sequentially one after the other, so that a continuous array is created in this way.
Step 2
Go to the cell, which should contain the correlation value of the data of the two arrays, and click the "Formulas" tab in the Excel menu. In the group of commands "Library of functions" click on the most recent icon - "Other functions". A drop-down list will open, in which you should go to the "Statistical" section and select the CORREL function. This will open the function wizard window with a form to fill out. The same window can be called up without the Formulas tab, simply by clicking on the function insert icon located to the left of the formula bar.
Step 3
Specify the first group of correlated data in the Array1 field of the Formula Wizard. To enter a range of cells manually, type the address of the first and last cells, separating them with a colon (no spaces). Another option is to simply select the required range with the mouse, and Excel will place the required record in this field of the form by itself. The same operation must be done with the second group of data in the "Array2" field.
Step 4
Click OK. The spreadsheet editor will calculate and display the correlation value in the formula cell. If necessary, you can save this document for future use (keyboard shortcut Ctrl + S).
