Measures of Central Tendencies and Variation

Front

What is the mean?

Back

The average of a set of numbers, calculated by adding all the numbers together and dividing by the count of numbers.

Front

What is the median?

Back

The middle value in a list of numbers sorted in ascending order. If there is an even number of observations, the median is the average of the two middle numbers.

Front

What is the mode?

Back

The number that appears most frequently in a data set.

Front

What is variance?

Back

A measure of how much the values in a data set differ from the mean, calculated as the average of the squared differences from the mean.

Front

What is standard deviation?

Back

A statistic that measures the dispersion of a dataset relative to its mean, indicating how spread out the values are.

Front

How do you calculate the mean of a data set?

Back

Add all the values together and divide by the number of values.

Front

How do you find the median in a data set?

Back

Sort the data in ascending order and identify the middle value.

Front

What is the formula for variance?

Back

Variance = (Σ(x - μ)²) / N, where μ is the mean and N is the number of observations.

Front

What is the difference between population and sample standard deviation?

Back

Population standard deviation uses N in the denominator, while sample standard deviation uses N-1 to account for sample size.

Front

What does a low standard deviation indicate?

Back

It indicates that the values in the data set are close to the mean.