Measures of Center/ Variability

Front

What is the mean of a set of numbers?

Back

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

Front

How do you calculate the mean of these numbers: 5, 11, 2, 12, 4, 2?

Back

Add the numbers: 5 + 11 + 2 + 12 + 4 + 2 = 36. Divide by the count (6): 36 / 6 = 6.

Front

What is the median?

Back

The median is the middle value of a data set when the numbers are arranged in order. If there is an even number of values, the median is the average of the two middle numbers.

Front

What is the mode?

Back

The mode is the number that appears most frequently in a data set.

Front

What is the interquartile range (IQR)?

Back

The IQR is the difference between the third quartile (Q3) and the first quartile (Q1) in a data set, representing the range of the middle 50% of the data.

Front

True or False: The IQR represents the range of the middle half of the data.

Back

True.

Front

What is the first quartile (Q1)?

Back

The first quartile (Q1) is the median of the lower half of a data set, representing the 25th percentile.

Front

What is the third quartile (Q3)?

Back

The third quartile (Q3) is the median of the upper half of a data set, representing the 75th percentile.

Front

How do you find the IQR of a data set?

Back

To find the IQR, subtract the first quartile (Q1) from the third quartile (Q3): IQR = Q3 - Q1.

Front

Which measure of center is best for skewed data?

Back

The median is the best measure of center for skewed data because it is not affected by extreme values.