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What does n-1 indicate in a calculation for variance?
The n-1 indicates that the calculation is being expanded from a sample of a population to the entire population. Bessel's correction(the use of n − 1 instead of n in the formula) is where n is the number of observations in a sample: it corrects the bias in the estimation of the population variance, and some (but not all) of the bias in the estimation of the population standard deviation. That is, when estimating the population variance and standard deviation from a sample when the population mean is unknown, the sample variance is a biased estimator of the population variance, and systematically underestimates it.
What difference between a favorable variance and an unfavorable variance?
Favourable variance is that variance which is good for business while unfavourable variance is bad for business
What is objectivity in statistics?
the use of random sampling that results in an unbiased conclusion.
What is the variance used for?
Variance is used to add standard deviations when comparing two samples or populations. Variance is simply Std^2. The formula for obtaining Std is dependent on the type of sample taken\ hypothesis test performed i.e. 2-proportion pop/sample, single proportion, poussin, binomial, etc.
What factors causes Budget Variance?
There are 7 variances associated with a budget ( which are generally calculated for controlling purposes) 1- Material Price variance 2- Material Quantity variance 3- Labor rate variance 4- Labor efficiency variance 5- Spending variance 6- Efficiency variance 7- Capacity variance
Is sample variance unbiased estimator of population variance?
No, it is biased.
Show that in simple random sampling the sample variance is an unbiased estimator of population variance?
It is a biased estimator. S.R.S leads to a biased sample variance but i.i.d random sampling leads to a unbiased sample variance.
What does it mean to say that the sample variance provides an unbiased estimate of the population variance?
It means you can take a measure of the variance of the sample and expect that result to be consistent for the entire population, and the sample is a valid representation for/of the population and does not influence that measure of the population.
Standard deviation considered a crude measure of variance?
No. Well not exactly. The square of the standard deviation of a sample, when squared (s2) is an unbiased estimate of the variance of the population. I would not call it crude, but just an estimate. An estimate is an approximate value of the parameter of the population you would like to know (estimand) which in this case is the variance.
What is the formula for calculating variance and standard deviation?
b-a/6
What is rao?
Rao is the guy who helped deelope th Rao Blackwell Theorem in 1945 it is the unique minimum variance unbiased estamator of its expected value
What has the author James D Malley written?
James D. Malley has written: 'Statistical applications of Jordan algebras' -- subject(s): Mathematical statistics, Jordan algebras 'Optimal unbiased estimation of variance components' -- subject(s): Estimation theory, Analysis of variance
In the presence of heteroscedasticity OLS estimators are biased as well as inefficient?
They are still unbiased however they are inefficient since the variances are no longer constant. They are no longer the "best" estimators as they do not have minimum variance
Is standard deviation biased or unbiased?
Standard deviation (SD) is neither biased nor unbiased. Estimates for SD can be biased but that depends on the formula used to calculate the estimate.
How do you find variance?
You calculate it using the appropriate formula, which, given the limitations of this site, is not easy to reproduce. However, you can easily Google the formula.
What does n-1 indicate in a calculation for variance?
The n-1 indicates that the calculation is being expanded from a sample of a population to the entire population. Bessel's correction(the use of n − 1 instead of n in the formula) is where n is the number of observations in a sample: it corrects the bias in the estimation of the population variance, and some (but not all) of the bias in the estimation of the population standard deviation. That is, when estimating the population variance and standard deviation from a sample when the population mean is unknown, the sample variance is a biased estimator of the population variance, and systematically underestimates it.
How do you use unbiased in a sentence?
The news anchor reported the story in an unbiased manner, presenting both sides equally.
