  I am trying to calculate class boundaries. When creating the class limits, they are all the same width but the last one and I can't figure out why. My guess is the starting point I am using. Is the starting point always the lowest data point?

Question

I am trying to calculate class boundaries. When creating the class limits, they are all the same width but the last one and I can't figure out why. My guess is the starting point I am using. Is the starting point always the lowest data point?

Step 1

Frequency distribution:

The number of values lying in the particular interval or the number of times each value repeats is the frequency of that particular class interval or event. The frequencies are calculated by using the tally mark.

Step 2

Procedure for obtaining class limits in a frequency distribution:

Step by step procedure for obtaining class limits in a frequency distribution is given below:

• The first lower class limit might be the minimum value or any number smaller than the minimum value of the dataset based on convenience.
• Consider the number of class intervals be n.
• Find the class width as (maximum value – minimum value)/ number of classes. Round up or round down the obtained class width if needed.
• Add the class width to the lower limit of the first class to get lower limit of the second class. Keep on doing this until the lower limit of the last class is obtained.
• Now, subtract 1 from class width and add the result to the lower limit of the first class to get upper limit of the first class. Continue the same procedure to find upper limits of all classes

Hence, the lower limit of the first class need not always be the lowest data point. It might be lowest data point or any value smaller than the lowest data point.

Step 3

Class boundaries:

Class boundaries are also called as actual class limits. The class boundaries of an interval will be the class limits in case of...

Want to see the full answer?

See Solution

Want to see this answer and more?

Our solutions are written by experts, many with advanced degrees, and available 24/7

See Solution
Tagged in

Statistics 