standard deviation

standard deviation : In probability theory and statistics, standard deviation is a measure of the variability or dispersion of a population, a data set, or a probability distribution. A low standard deviation indicates that the data points tend to be very close to the same value (the mean), while high standard deviation indicates that the data are spread out over a large range of values. For example, the average height for adult men in the United States is about 70 inches (178 cm), with a standard deviation of around 3 in (8 cm). This means that most men (about 68 percent, assuming a normal distribution) have a height within 3 in (8 cm) of the mean (67–73 in (170–185 cm)), while almost all men (about 95%) have a height within 6 in (15 cm) of the mean (64–76 in (163–193 cm)). If the standard deviation were zero, then all men would be exactly 70 in (178 cm) high. If the standard deviation were 20 in (51 cm), then men would have much more variable heights, with a typical ran....   More from Wikipedia

standard deviation : In probability theory and statistics, the geometric standard deviation describes how spread out are a set of numbers whose preferred average is the geometric mean. If the geometric mean of a set of numbers { A 1, A 2, ..., A n} is denoted as μ g, then the geometric standard deviation is If..   More from Wikipedia

  This is the third sample video from the 10 hour "Probability and Statistics Tutor" DVD available at MathTutorDVD.com. This clip introduces the concept of standard deviation.

  If you found this video helpful, please consider a contribution, www.paypal.com

Question : what is standard deviation a measure of? I've worked it out for some sets of data, and I think that it is a measure of spread, but I'm not exactly sure. is around 20 high when im working with numbers around 500mm, and 15 when im working with numbers around 200mm (these are hand and head sizes)

Answer : Standard deviation is a measure of deviation from a reference value (mean) of certain values of a sample. This is calculated as follows, s = squreroot{ E(x^2) - E(x)^2} where E(x) = expected value of "x"..   More from Yahoo Answers

Question : I understand how to get the standard deviation for a stock by going through the variance. What I'm curious about is how to convert the stocks standard deviation into the stocks beta value. Also what is considered a low volatile stock as far as standard deviation goes? I know with the beta anything higher than 1.0 is considered highly volatile. Any information on this subject would be greatly appreciated.

Answer : This is an excellent tutorial that someone else posted on how to calculate beta using Excel. A beta higher than one doesnt necessarily mean a stock is highly volatile. It just means the returns are more volatile than the market. Beta is the risk that is added to a diversified portfolio...   More from Yahoo Answers

Looking for More Help!

Type Your Question Here