Fitting a sigmoidal curve to data on a chart using Microsoft Excel

1. First, make sure your data is organized in two columns: one for the x-axis values and one for the y-axis values.
2. Select the data you want to use for the curve fit.
3. Click on the "Insert" tab in the Excel ribbon and select "Scatter" from the chart options.
4. Choose the scatter chart type that includes lines connecting the data points.
5. Right-click on one of the data points and select "Add Trendline" from the context menu.
6. In the "Format Trendline" pane that appears on the right side of the screen, select "Logistic" as the trendline type.
7. Adjust the other trendline options as desired, such as the line color and thickness.
8. Click "Close" to apply the trendline to the chart.

Your chart should now display a sigmoidal curve that fits the data. You can use this curve to make predictions or analyze the relationship between the x and y variables.

Using Solver. I show the use of Solver to fit a function at
http://people.stfx.ca/BLIENGME/ExcelTips/Elisa.mht
with sample worksheet.
If you wish, you may send me (get my email address from my website) a file
with data and the function to be fitted
best wishes
--
Bernard Liengme
MVP Excel
http://people.stfx.ca/bliengme

"tp" wrote in message
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