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How do you find expectation and variance of a variable using moment generating functions?
Wiki User
∙ 13y ago
The derivative of the moment generating function is the expectation. The variance is the second derivative of the moment generation, E(x^2), minus the expectation squared, (E(x))^2.
ie var(x)=E(x^2)-(E(x))^2
:)
Wiki User
∙ 13y ago
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What is the variance for the uniform random variable?
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What a correlation of 0.30 means that the independent variable explains -- percent of the variance in the dependent variable?
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What is the variance for the uniform random variable?
the variance of the uniform distribution is (a+b)/12
What a correlation of 0.30 means that the independent variable explains -- percent of the variance in the dependent variable?
The independent variable explains .32*100 percent of the variance in the dependent variable.This is 9%.The explainable variance is always the square of the correlation (r).
How do you find the z score of 12.5?
To find the Z score from the random variable you need the mean and variance of the rv.To find the Z score from the random variable you need the mean and variance of the rv.To find the Z score from the random variable you need the mean and variance of the rv.To find the Z score from the random variable you need the mean and variance of the rv.
What does homogeneity of variance mean?
It means that the variance remains the same across the range of values of the variable.
What is Proportion of variance unaccounted?
The unaccounted for variance aka Error Variance, is the amount of variance of the dependent variable (DV) that is not accounted for by the main effects/independent variables (IV) and their interactions.
What is the difference between the coefficient of simple determination and that of multiple determination?
The coefficient of simple determination tells the proportion of variance in one variable that can be accounted for (or explained) by variance in another variable. The coefficient of multiple determination is the Proportion of variance X and Y share with Z; or proportion of variance in Z that can be explained by X & Y.
What is a variance covariance matrix?
Briefly, the variance for a variable is a measure of the dispersion or spread of scores. Covariance indicates how two variables vary together. The variance-covariance matrix is a compact way to present data for your variables. The variance is presented on the diagonal (where the column and row intersect for the same variable), while the covariances reside above or below the diagonal.
In analysis of variance the term factor refers to?
independent or quasi-independent variable
What causes variance in the criterion variable?
Let me guess...stats comps, too?
