• Equation:

Mean

Example data:

DBH (in) Count Sum

5 6 30

6 11 66

7 17 119

8 20 160

9 19 171

10 11 110

SUM 84 656

Mean = 7.81

Mode

MedianDBH (in)

10

9

8

11

12

50

Tree Count (# Trees)

# Occurances

0 186

1 185

2 102

3 23

4 4

1000 1

Mean = 0.948Median = 1

If we have that 1000Mean = 2.942Median = 1

Range• Largest Value – Smallest Value• Gets the extreme values

Standard Deviation

Coefficient of Variation

DBH (in)

8

10

12

15

9

13

MEAN: 11.17”

SD: 2.64”

Homework Problem

• Find mean, mode, median, range, standard deviation, and coefficient of variation of the following tree height data (feet)

• 60, 75, 66, 83, 59, 91, 66, 78, 84, 100, 73, 66, 75