# The Definition of Mean Difference

Save

Mean difference is a mathematical term. You will also commonly hear it referred to as an average. It represents a generalized central value of a data set -- for example, the central value of a series of numbers.

## Calculating Mean Difference

• Add up the numbers, or value sets, in your series and then divide that sum by the number of value sets. For example, if you are calculating the average number of eggs your hen lays in five days, track the number of eggs she lays on each day: Monday, 2 eggs; Tuesday, 1 egg; Wednesday, 3 eggs; Thursday, 2 eggs; Friday, 2 eggs. The total number of eggs is 10. Divide 10 by the number of days you tracked her laying, which is 5. 10 eggs divided by 5 days equals a mean or average of 2 eggs per day.

## Means Versus Median

• Don’t confuse mean difference with median, which is similar to the mean but measures a tendency based on the center of the value. To calculate the median, list your daily egg totals from highest to lowest. 3, 2, 2, 2, 1. The median point is the number from which 50 percent of your eggs came before, and 50 percent after. So in this case, that's 2. Your hen has a tendency to lay 2 eggs per day. You can also list the values from lowest to highest. In this example the mean and median are the same, but that's coincidence. They usually will be different values.

## References

• Photo Credit nineeak/iStock/Getty Images
Promoted By Zergnet

## Resources

### You May Also Like

• Define Mean for Math

In math, the mean is the average of a set of numbers. To find the mean of a data set, add up...

• Difference Between the Mean & the Average

In mathematics, "average" refers to a specific arithmetic calculation, while "mean" can be synonymous with "average" or refer to an entirely different...

• Definition of Mean, Median & Mode

Whether you are a math student, survey taker, statistician or researcher, you are going to need to calculate the average of multiple...

• What Does a Negative T-Value Mean?

Researchers and scientists often use statistical tests called t-tests to assess whether two groups significantly differ from one another. T-tests take into...

• What Is the Mean Percentage Difference?

Mean percentage difference is the average of the percentage differences between two results observed over a set number of times. You might...

• How to Calculate Mean Differences

Calculating the mean difference of a series of numbers is a simple process, as the mean is essentially the average number in...

## Related Searches

Check It Out

### Are You Really Getting A Deal From Discount Stores?

M
Is DIY in your DNA? Become part of our maker community.