I have measured the diameter and circumference of various (ca. 50) circular objects and would like to plot the ratio, i.e., circumference:diameter in order to show that those values are close to pi.
How can I do that? I am not asking for technical help but rather on the best way to present the data to laymen.
One difficulty might be that several numbers are identical and I do want to distinguish this, i.e. if I have three times the value 3.2 that should be graphically distinct from just once the same value.
One way to present this would be in a bar diagram, but I want something more direct, without (randomly chosen) intervals.
The normal way, of plotting circumference vs diameter and getting pi from the slope is unfortunately no option, because the audience does not know about the concept of "slope".
If you plot the circumference on the Y axis against the diameter on the X axis you should see an approximately linear relationship between the two.
Since $C=\pi D$, the line of best fit for the data should have a slope of approximately $ \pi$. Hope that helps.