Table of Contents
- 1 What is the correlation coefficient between X and Y?
- 2 What is the difference between a standard normal distribution in a non standard normal distribution?
- 3 Which of the following properties distinguishes the standard normal distribution from other normal distributions?
- 4 Is the correlation coefficient a standard measure of relationship?
What is the correlation coefficient between X and Y?
The correlation of X and Y is the normalized covariance: Corr(X,Y) = Cov(X,Y) / σXσY . The correlation of a pair of random variables is a dimensionless number, ranging between +1 and -1.
What is correlation coefficient between two random variables?
The correlation coefficient is a statistical measure of the strength of the relationship between the relative movements of two variables. The values range between -1.0 and 1.0. A calculated number greater than 1.0 or less than -1.0 means that there was an error in the correlation measurement.
How do you find the correlation between two random variables?
2 The correlation of X and Y is the number defined by ρXY = Cov(X, Y ) σXσY . The value ρXY is also called the correlation coefficient. Theorem 4.5. 3 For any random variables X and Y , Cov(X, Y ) = EXY − µXµY .
What is the difference between a standard normal distribution in a non standard normal distribution?
The standard normal distribution has a mean of 0 and a standard deviation of 1, while a nonstandard normal distribution has a different value for one or both of those parameters.
How you can transform a nonstandard normal distribution to the standard normal distribution?
To transform a nonstandard normal distribution to the standard normal distribution you must transform each data value x into a z-score.
What does it mean if AZ score is 0?
Z-score is measured in terms of standard deviations from the mean. If a Z-score is 0, it indicates that the data point’s score is identical to the mean score. A Z-score of 1.0 would indicate a value that is one standard deviation from the mean.
Which of the following properties distinguishes the standard normal distribution from other normal distributions?
Standard Normal Distribution is symmetric continuous distribution with mean 0 and variance 1. -The mean is located at the center of the distribution. This is True because here the center of the distribution is 0 and the mean is also 0. -The total area under the curve is equal to 1.00.
Why can the normal distribution be used even though the sample size does not exceed 30?
Why can the normal distribution be used in part (b), even though the sample size does not exceed 30? Since the original population has a normal distribution, the distribution of sample means is a normal distribution for any sample size.
Is x normally distributed as a chi-square random variable?
The following theorem clarifies the relationship. If X is normally distributed with mean μ and variance σ 2 > 0, then: is distributed as a chi-square random variable with 1 degree of freedom.
Is the correlation coefficient a standard measure of relationship?
The correlation coefficient is a standardized measure and is a measure of linear relationship between the two random variables. The following theorem makes this clear. For any two random variables and , the following statements are true.
When X and Y have the bivariate normal distribution with zero correlation?
To understand that when X and Y have the bivariate normal distribution with zero correlation, then X and Y must be independent. To understand each of the proofs provided in the lesson. To be able to apply the methods learned in the lesson to new problems.
What does the covariance of X and y necessarily reflect?
The covariance of X and Y necessarily reflects the units of both random variables. It is helpful instead to have a dimensionless measure of dependency, such as the correlation coefficient does. Let X and Y be any two random variables (discrete or continuous!) with standard deviations σ X and σ Y, respectively.