Measures of Variability - Page 3

Questions
  • Why can't variance be negative?
  • What is the difference between a sample and population variance?
  • Of the range and the standard deviation, which is more widely used in statistical analysis, and why?
  • What is the mathematical formula for the variance of a continuous random variable?
  • What is the lower bound of a random variable's variance?
  • If you are examining the height of a population, how would the variation be affected if everyone is wearing platform shoes that are exactly 3 inches tall?
  • What is the symbol for the sample standard deviation?
  • What is the formula for the variance of a geometric distribution?
  • What is the variance of X if it has the following probability density function?: f(x) = { 3x2 if -1 < x < 1; 0 otherwise}
  • Why is variance invariant with regards to translation?
  • What are the variance and standard deviation of a binomial distribution with #N=124# and #p=0.85#?
  • How does the covariance between two variables affect the variance of their sum?
  • How do you find the covariance of a continuous probability density function?
  • How do you calculate the covariance between two discrete variables?
  • If Corr(X,Y) = 0, does Cov(X,Y) = 0?
  • What is a sample covariance?
  • What is the difference between a correlation matrix and a covariance matrix?
  • Is there a difference between a correlation and a correlation coefficient?
  • What is the variance of 10 coin flips?
  • What is the difference between the population standard deviation and the sample standard deviation?