Estimated Mean from Grouped Data Flashcards

Data that is organised into intervals or classes, often used when there is a large amount of data.

The value halfway between the lower and upper boundaries of a class interval.

The number of data points that fall within a particular class interval.

The product of the frequency and the midpoint for each class interval, used to calculate the total of the data values.

Estimated mean = (Σ(frequency × midpoint)) ÷ (Σfrequency).

The sum of all the products of frequency and midpoint across all class intervals.

The total frequency, which is the sum of all frequencies across the class intervals.

The mean is estimated because the exact data values within each class interval are unknown, so the midpoint is used as an approximation.

1. Find the midpoint of each class. 2. Multiply each midpoint by its frequency. 3. Add these products to get Σ(frequency × midpoint). 4. Divide by Σfrequency.

To provide an approximate average value for a dataset when the exact data values are not available.