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Covariance defined
Message posted by G Colassi on October 27, 2000 at 12:00 AM (ET)
I cannot find a definition of covariance and how it differs from correlation. I found is a mention of crossproducts but little explanation what crossproducts are as compared to products? Could anyone kidly sort this for me? Thanks!
READERS RESPOND:
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Re: Covariance defined
Message posted by SOF on October 27, 2000 at 12:00 AM (ET)
When covariance is scaled to become dimensionless, it becomes correlation. See any introductory statistics book for details.
Re: Covariance defined
Message posted by Phil on October 29, 2000 at 12:00 AM (ET)
Covariance is a measure of how much two variables move together. Just the covariance by itself is not always a helpful number. When divided by a "pooled variance" of the two variables, you can derive correlation. Correlation is often more useful for understanding the relationship between two variables.Almost any statistics book should explain this. If your book doesn't, pick up almost any other one and look. It should also be on the web. Try looking around at: interactive web pages
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