Encyclopedia of Autism Spectrum Disorders

2013 Edition
| Editors: Fred R. Volkmar

Normal Curve

  • Marc J. TasséEmail author
  • Matthew Grover
Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-1698-3_1745



The normal curve represents the shape of an important class of statistical probabilities (see Fig. 1below). The normal curve is used to characterize complex constructs containing continuous random variables. Many phenomena observed in nature have been found to follow a normal distribution. Some human attributes such as height, weight, intelligence, and even social skills can be said to be normally distributed. For example, most people’s height clusters around the population mean, and an equally small proportion of people, are represented at either extreme end of the distribution. When represented graphically, the resulting shape resembles that of a bell where there is a single peak at the mean, while the tails extend to the right and left into infinity. Thus, the probability of being 5′10″ is relatively high, while the probability of being 7′4″ is much smaller. Raw data from any number of...
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References and Readings

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  5. Keppel, G., & Wickens, T. D. (2004). Design and analysis: A researcher’s handbook (4th ed.). Upper Saddle River, NJ: Pearson Prentice Hall.Google Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Nisonger Center – UCEDD, Departments of Psychology and PsychiatryThe Ohio State UniversityColumbusUSA
  2. 2.Nisonger Center - UCEDDThe Ohio State UniversityColumbusUSA