{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Descriptive Statistics

# Descriptive Statistics - 1 2 2 N x N i i ∑ = − = σ...

This preview shows pages 1–2. Sign up to view the full content.

1 Descriptive Statistics Objectives: (Chapter 3, Decoursey) - To understand the definition of , median, variance, standard deviation, mean absolute deviation and coefficient variation and calculate these quantities. - To calculate some of these quantities using the statistical functions of . Descriptive Statistics Arithmetic Mean: = i x N or x 1 μ is the mean of a sample. x is the mean of a population. μ N is the total number of data points. i x is the i th data point in the sample or population. Descriptive Statistics Median: If all the items with which we are concerned are sorted in order of increasing (size), from the smallest to the largest, then the median is the middle item. If the number of the items is odd, the median is the middle item. e.g. 12, 13, 21, 27, 31 The median is . If the number of the items are even, the median is given by the arithmetic mean of the two middle items. e.g. 12, 13, 21, 27, 33, 37 The median is (21+27)/2=24. Descriptive Statistics

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document