variance

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Related to Sample variance: population variance

Variance

A measure of dispersion of a set of data points around their mean value. The mathematical expectation of the average squared deviations from the mean. The square root of the variance is the standard deviation.

Variance

1. In accounting, the difference between the estimated and actual cost of a project or other operation.

2. In risk, the average deviation of a set of data points from their mean.

variance

A statistical measure of the variability of measured datum from the average value of the set of data. A high variance, indicating relatively great variability, also indicates that the average is of minimal use in projecting future values for the data. Standard deviation is the square root of variance. Financial analysts use both statistical measures to weigh investment risk. Compare covariance. See also risk.

variance

  1. the difference between budgeted and actual results (see BUDGETING), or between STANDARD COSTS/revenues and actual costs/revenues. Variances can be:
    1. adverse or negative when actual revenues fall short of budget or standard, or when actual costs exceed budget or standard;
    2. favourable or positive when actual revenues exceed budget or standard, or when actual costs are less than budget or standard.
    3. a measure of variation within a group of numerical observations, specifically the average of the squared deviations of the observations from the group AVERAGE.

      See STANDARD DEVIATION.

variance

Permission to use a property in a manner that does not meet current zoning requirements.In order to gain a variance,the property owner usually has to show a hardship on the property—not on the owner—if the requested use is not allowed. It is considered a hardship if the property will otherwise remain vacant or if a structurally sound improvement must be demolished to allow some other use. Buyers with a signed purchase contract can usually petition for a variance; this is commonly one of the steps in a due diligence plan that must be completed in a satisfactory manner before the buyer will purchase property.

References in periodicals archive ?
For the comparison, the sample variance from srswor based on E(v) has variance using the formula:
and the variance of U/N is approximated by the large sample variance formula for a ratio.
The sample variance was not statistically different between the two groups of respondents.
If the sample variance is unbiased, then approximately half of the estimates will exceed the true variance and, therefore, the planning variance, leading to achieved precision larger than planned precision.
For example, Chapter 8 misdefines the sample variance (p.
These distributions allow a reseacher to make inferences about the values of unknown population means by using the sample variance as a proxy for the population variance, when the population variance is unknown.
Measuring the effect of washing was made difficult by the high level of sample to sample variance (std.
The design effect indicates the factor by which simple random sample variance calculations need to be increased to correct for clustering.
In view of the imprecision of parameter settings, Shiffler and Harwood (1985) investigated the effect on the realized [alpha]-risk of using a pilot sample variance to estimate variance on the sample size formula for testing population means.
It is noted that the proposed approach typically results (without loss of accuracy) in a smaller number of total samples (using the sample size formula as given in EPA [8]) than that obtained by using the sample variance of the entire dataset from the site under study.