Descriptive Statistics(1)(1)

Descriptive Statistics(1)(1) - Descriptive Statistics Click...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style 3/20/11 Descriptive Statistics
Background image of page 1

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

View Full DocumentRight Arrow Icon
3/20/11 Descriptive Stats Descriptive statistics are used to describe data, i.e., descriptive statistics are used to summarize data in order to communicate information about the data set in a concise manner. measures of center measures of variation measures of position
Background image of page 2
3/20/11 Measures of Center Measure of Center Value at the ‘middle’ of a data set Mean Median Mode
Background image of page 3

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

View Full DocumentRight Arrow Icon
3/20/11 Measures of Center Mean (Arithmetic) The sum of all the values divided by the total number of values Population Sample N x = μ n x x =
Background image of page 4
3/20/11 Measures of Center Median The middle value when the data are ordered If there are an even number of values, then median is the average of the two middle values e.g, if there are 20 values, the median is the average of the 10th and 11th values If there are an odd number of values, x ~
Background image of page 5

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

View Full DocumentRight Arrow Icon
3/20/11 Measures of Center Mode The value(s) that repeated most often If no value is repeated, the mode does not exist The mode may have more than one value
Background image of page 6
3/20/11 Measures of Center Which measure is best? The mean and median are the most commonly used The mean is affected by extreme values, while the median is not The mean takes all values into account The mean is the most reliable (varies the least) The mean is the basis for many
Background image of page 7

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

View Full DocumentRight Arrow Icon
3/20/11
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 31

Descriptive Statistics(1)(1) - Descriptive Statistics Click...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online