1. Find the arithmetic mean (mathematical expectation) xi and standard deviation si of each variable (index).
2. Standardization, xij = (xij-xi)/si, xij = is the standardized variable value; Sigi is the actual variable value.
3. Reverse the symbol before the indicator.
Extended data
1. Starting from the input font adjustment, we can find the font adjustment toolbox in the toolbar "Start" menu module, where we can quickly change the font type, size, color and so on.
2. Before typing or typing, you need to adjust the font alignment according to a certain format. In the alignment toolbar, you can quickly change the font alignment.
3. If you want to input some data for consumption statistics, then you should input the symbol "RMB", which is too troublesome. You should input it repeatedly and directly in the number box.
4. Insert and delete cells. In the cell toolbox, we can quickly insert or delete cells with one click.
5. Common functions can be completed with one click and found directly in the tool.
6. If you want to know the sum or average of some numbers directly, you can know by directly selecting those numbers.
7. The use of the format brush is very simple. Just click the format brush, then select the format to copy, and finally select the cell to modify, and you can modify it in batches.
8. Excel tables can be made into tables with one click. Select some data, then select Insert in the toolbar above, and then open the chart.
Source: Baidu Encyclopedia -excel