How to build a cumulate
Video: Excel Cumulative Sum Formula 2024, July
One way to study the distribution series is to build cumulates. It allows you to graphically depict the dependence of the value of the sign on the accumulated frequency. Most often, a cumulate, or a polygon of accumulated frequencies, is used to represent discrete data.
You will need
- - discrete variation series;
- - ruler;
- - a pencil;
- - eraser.
Instruction manual
one
Bring the available data in the form needed to build a graph. Divide the sample into equal parts to get a uniform position of the points in the graph. Most often, the division into time intervals is used for this: months, days, years. To use this method, calculate the value of the characteristic for each period of time, for example, how many product units were sold in each month. If the trait varies weakly and discretely, use a non-interval variational series (this may be, for example, student grades).
2
Enter the data in the table, you get two lines: in the first indicate the intervals or intervalless values, and in the second - the frequency of the characteristic found. Add one more line - the accumulated frequency of the characteristic value. Fill in this column by sequentially adding frequencies from the second row. For example, if 5, 3, 4 units of equipment were sold consecutively in each month of the quarter, then the accumulated frequency will be 5, 5 + 3, 5 + 3 + 4, that is, 5, 8, 12. Please note that each subsequent value of the accumulated frequency will always be equal to or greater than the previous one, so the chart will never go down.
3
Build a coordinate system. On the abscissa axis, place the attribute values, and on the ordinate axis, place the accumulated frequencies. Indicate the name and unit of measure next to the axis.
4
Set the dots according to your table. To do this, use the values of the first and third lines, the line "characteristic frequency" will not participate in the construction. Measure the value of the trait on the abscissa axis, the accumulated frequency on the ordinate axis, and put a dot at the intersection. When all the points are built, connect them with a broken line. This line is called the cumulative distribution series.
5
To build a cumulate in Excel, enter data in rows or columns, then click Insert - Chart. Choose one of the suitable scatter charts, specify the data you need to build (do not forget, only two lines - the value of the characteristic and the accumulated frequency) and click "finish". If necessary, correct the finished diagram using the settings window.