Effect of varying number of bars

The number of classes used in a histogram plot will almost always affect the relative frequency (but not probability density) scale of the y-axis. Clearly, the wider the bar width, the more chance there will be that values will fall within it. So, for example, by doubling the number of histogram bars, the relative frequency scale will approximately halve.

In plotting a histogram, the number of bars should be chosen to balance between a lack of detail (too few bars, on the left) and overwhelming random noise (too many bars, on the right).

When the result of a risk analysis model is a discrete distribution, you will need to experiment with the number of histogram bars to get the best plot. If possible set the number of bars to be some multiple of the number of allowed values in your distribution; as this will prevent interference patterns:

See Also

 

ModelRisk

Monte Carlo simulation in Excel. Learn more

Tamara

Adding risk and uncertainty to your project schedule. Learn more

Navigation

FREE MONTE CARLO SIMULATION SOFTWARE

For Microsoft Excel

Download your free copy of ModelRisk Basic today. Professional quality risk modeling software and no catches

Download ModelRisk Basic now

FREE PROJECT RISK SOFTWARE

For Primavera & Microsoft Project

Download your free copy of Tamara Basic today. Professional quality project risk software and no catches.

Download Tamara Basic now
-->