How to Determine the Number of Classes for a Histogram?

To determine the number of classes needed to construct a histogram for the given data set, we can use Sturges’ formula, which is a common method in statistics. Sturges’ formula is given by:

Number of Classes (k) = 1 + log2(N)

Where N is the total number of observations in the data set.

In this case, let’s first count the number of data points in your list:

• Given data: 34, 51, 19, 23, 47, 45, 37, 49, 25, 17, 51, 30, 37, 46, 39, 36, 12, 47, 40, 31, 26, 47, 14, 41, 22, 39, 15, 16
• Total observations (N): 28

Now, we will apply Sturges’ formula:

Number of Classes (k) = 1 + log2(28)

Using a calculator, we find:

log2(28) ≈ 4.807

So, plugging this value back into our formula gives us:

K ≈ 1 + 4.807 ≈ 5.807

Since the number of classes must be a whole number, we round this to 6.

Thus, the number of classes needed to construct a histogram for the provided data is 6.