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 ?
Note that the sample variance for lead based upon a sample of 30 observations is 3375.
60 5 1 290 * Table 4: Sample sizes for lead by sub-populations Sub-population Sample Variance Sample Size n 1 0.
Mixing theory allows us to predict the effect of the sample size upon the normalized sample variance for a limited number of classic morphologies.
Improving small sample variance estimators for bounded random variables.
We used a Levene test to check homogeneity of sample variances and Tukey-Kramer multiple-comparisons and a t-test to determine if canonical variate (CV) 1 differed significantly among and between samples.
A modified version of this, called the O'Brien test, can be used, which creates a dependent variable so the group means of the new variable equal the group sample variances of the original responses.
The idea in this approach is that social interactions will induce intragroup dependences in behavior that affect sample variances for intragroup outcomes.
Taylor (1961) reported the following empirical result of the distributions of populations with multiple sampling: if the logarithms of the sample variances are plotted against the logarithms of the sample means for several samples, then these points define a nearly straight line.
2]) are unknown, but they can be computed based on the sample variances ([s.