The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
The arithmetic mean, or as it is sometimes referred to, the average of a data set, is the sum of all data values divided by the number of items in the set. A mean is considered to be a measure of central tendency--it describes a "typical" value to represent the data set. It describes or gives a summary of a whole distribution of events or measurements. The information given by measures of central tendency can be used for description or comparison.
An example of finding an arithmetic mean using a particular data set is as follows: in the set 1, 2, 5, 10, 12, 14, 16, 17, 20 the mean is calculated as 1 + 2 + 5 + 10 + 12 + 14 + 16 + 17 + 20 ÷ 9 = 10.8. It is very likely that the mean will be a number not directly represented in the data set. However, every number in the data set affects the mean. If an "outlier" (a data value very unlike the rest) is present, the mean can misrepresent the data set. One symbol often used for mean is . The arithmetic mean is the most common measure used for central tendency--the others being median and mode.
The geometric mean, m, of two numbers (x and y) is the square root of their product. x ÷ m = m ÷ y or m = xy. The geometric mean is also referred to as the geometric proportional. It is used in geometry to find the lengths of sides in similar triangles using the altitude.