Standard error of the mean (SEM) and standard deviation of the mean is the same thing. However, standard deviation is not the same as the SEM. To obtain SEM from the standard deviation, divide the standard deviation by the square root of the sample size.
The standard deviation is the standard deviation! Its calculation requires no assumption.
The standard deviation is always be equal or higher than zero. If my set of data is limited to whole numbers, all of which are equal, the standard deviation is 0. In all other situations, we first calculate the difference of each number from the average and then calculate the square of the difference. While the difference can be a negative, the square of the difference can not be. The square of the standard deviation has to be positive, since it is the sum of all positive numbers. If we calculate s2 = 4, then s can be -2 or +2. By convention, we take the positive root.
The square of the standard deviation is called the variance. That is because the standard deviation is defined as the square root of the variance.
Mean 0, standard deviation 1.
How can the return and standard deviation of a portfolio be deteremined
we calculate standard deviation to find the avg of the difference of all values from mean.,
Standard error of the mean (SEM) and standard deviation of the mean is the same thing. However, standard deviation is not the same as the SEM. To obtain SEM from the standard deviation, divide the standard deviation by the square root of the sample size.
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The mean is the average value and the standard deviation is the variation from the mean value.
Standard error is the difference between a researcher's actual findings and their expected findings. Standard error measures the accuracy of one's predictions. Standard deviation is the difference between the results of one's experiment as compared with other results within that experiment. Standard deviation is used to measure the consistency of one's experiment.
If I have understood the question correctly, despite your challenging spelling, the standard deviation is the square root of the average of the squared deviations while the mean absolute deviation is the average of the deviation. One consequence of this difference is that a large deviation affects the standard deviation more than it affects the mean absolute deviation.
For a two-asset portfolio, the risk of the portfolio, σp, is: 2222p1122112212222p11221212121212σ=wσ+wσ+2wσwσρorσ=wσ+wσ+2wwcovcov since ρ=σσ where σi is the standard deviation of asset i's returns, ρ12 is the correlation between the returns of asset 1 and 2, and cov12 is the covariance between the returns of asset 1 and 2. Problem What is the portfolio standard deviation for a two-asset portfolio comprised of the following two assets if the correlation of their returns is 0.5? Asset A Asset B Expected return 10% 20% Standard deviation of expected returns 5% 20% Amount invested $40,000 $60,000
For a two-asset portfolio, the risk of the portfolio, σp, is: 2222p1122112212222p11221212121212σ=wσ+wσ+2wσwσρorσ=wσ+wσ+2wwcovcov since ρ=σσ where σi is the standard deviation of asset i's returns, ρ12 is the correlation between the returns of asset 1 and 2, and cov12 is the covariance between the returns of asset 1 and 2. Problem What is the portfolio standard deviation for a two-asset portfolio comprised of the following two assets if the correlation of their returns is 0.5? Asset A Asset B Expected return 10% 20% Standard deviation of expected returns 5% 20% Amount invested $40,000 $60,000
The standard deviation is the standard deviation! Its calculation requires no assumption.
Standard deviation; correlation coefficient
The standard deviation of the population. the standard deviation of the population.