Measures of Variance

The heights of six students in a class are given below:
158cm     172cm      164cm
164cm     167cm      159cm
 However, there were actually seven students in the class, and the mean height in the class was 165 cm. What was the height of the unknown student?

• 164 cm
• 166 cm
• 171 cm
• 169 cm

What is the standard deviation for the data given:
5, 10, 7, 12, 0, 20, 15, 22, 8, 2

• 6.89
• 10.1
• 7.26
• 9

What is the variance for the data given:
5, 10, 7, 12, 0, 20, 15, 22, 8, 2

• 47.47
• 102.01
• 52.77
• 81

Which of the following is a measure of variability?

• mean
• median
• mode
• standard deviation

If the standard deviation of a data set is 4, what is the variance?

• 2
• 16
• 4

What does this symbol represent?

• Variance
• Standard Deviation
• Mean Absolute Deviation
• Sigma

What does variance represent?

• How many different variations are in the data set.

• How the population varies compared to the sample.

• How spread out each data value is from the mean.

• The range, but with a bunch of other stuff going on.

Before you can begin calculating the variance, you must first:

• find the mean

• find the median

• find the mode

• find the range

How do you calculate the standard deviation?

• Divide the variance by 2.

• Its a long process and I can't explain it right now.

• Find the mean and multiply it by the variance.

• Take the square root of the variance.

What does this symbol represent?

• Standard Deviation
• Variance
• Mean Absolute Deviation
• Sigma