## Easy data collection in GeoGebra and regression analysis

To the left you see a GeoGebra activity in which you can first import a digital image and then place data points on the image to approximate a curve. When you do this, a table with the x- and y-coordinates of the data points will appear. You can copy the table entries to the clipboard, in which case you have to option to choose between the comma or the point as notation for decimal numbers. You can drag a data point another location (e.g., to improve the quality of the data collection), but then you mustpress the refresh button to update the table. Three types of regression are provided: linear, quadratic and cubic function fit. When you press any of the regression toolbuttons, the computed regression curve is displayed in the GeoGebra activity to the left of the page.