Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Variance


Related Topics

  
  PlanetMath: variance
This formula is often used to calculate variance analytically.
The variance can also be characterized as the minimum of expected squared deviation of a random variable from any point:
This is version 9 of variance, born on 2001-10-26, modified 2007-07-08.
planetmath.org /encyclopedia/Variance.html   (229 words)

  
 STD 06-00-001 - STD 6.1 - Variance Policy and Procedures
Variance inspection will be required when making decisions on adequate variance requests involving flammable and combustible liquids, toxic and carcinogenic substances, explosives, electrical equipment and others as deemed necessary.
Variance inspections will also be required for temporary and experimental variances, for situations involving employee objection to the variance, or where first-hand examination is necessary to obtain further information.
Temporary variances are technically available only during that period between promulgation of a standard and its effective date for employers unable to come into compliance within that time.
www.osha.gov /pls/oshaweb/owadisp.show_document?p_table=DIRECTIVES&p_id=1826   (1298 words)

  
 Legal Definition of Variance
Variances are between the writ and the declaration, and between the declaration and the evidence.
A variance by disagreement in some particular point or points only between the allegation and the evidence, when upon a material point, is as fatal to the party on whom the proof lies, as a total failure of evidence.
This was held to be a variance, because the additional words were material, and qualified the effect of the contract.
www.lectlaw.com /def2/u082.htm   (260 words)

  
  Variance Components   (Site not responding. Last check: )
The variance components are mainly used, at least in educational research, as indicators of existing variation between contexts.
Used this way, variances are considered to be nuisances or errors, and usually not reported, unless to show a reduction in variance due to the adding of second level variable(s).
The first study [Busing(1993)] reports the behavior of variance components estimated by an unrestricted methods (IGLS) The second study, [van der Leeden and Busing(1994)] reports the results of a restricted estimation method (RIGLS), which is equivalent to REML used in the software HLM.
www.calstatela.edu /faculty/ikreft/quarterly/node15.html   (1120 words)

  
  Standard Deviation and Variance: Common Measures of Variability
The variance and the closely-related standard deviation are measures of how spread out a distribution is. In other words, they are measures of variability.
The variance is computed as the average squared deviation of each number from its mean.
The formula (in summation notation) for the variance in a population is
www.davidmlane.com /hyperstat/A16252.html   (305 words)

  
  Variance - Wikipedia, the free encyclopedia
is a biased estimator of the population variance.
of the population variance, or to the variance σ
is an unbiased estimator of the population variance.
en.wikipedia.org /wiki/Variance   (1155 words)

  
 Allan variance - Wikipedia, the free encyclopedia
It is defined as one half of the time average of the squares of the differences between successive readings of the frequency deviation sampled over the sampling period.
The Allan variance depends on the time period used between samples: therefore it is a function of the sample period, as well as the distribution being measured, and is displayed as a graph rather than a single number.
Allan variance is used as a measure of frequency stability in a variety of exotic precision oscillators, such as frequency-stabilized lasers.
en.wikipedia.org /wiki/Allan_variance   (315 words)

  
 06/07/1995 - Variance request.
One of these variance requests is with respect to 1910.107(h)(6) which requires that a safe distance must be maintained between goods being painted and electrodes or electrostatic atomizing heads or conductors of at least twice the sparking distance.
FMC requested this variance "to permit it to continue operating in accordance with the recommendations of the manufacturers of the electrostatic spray painting equipment it uses" in unmanned zones.
The other variance requested by FMC is with respect to 1910.107(h)(8) which prohibits the manipulation by hand of goods that are being coated by fixed electrostatic spraying equipment.
www.osha.gov /pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=21825   (882 words)

  
 Subject Top Page: Variance Oversight Program
pertaining to the grant of a variance are met, and that compliance with emission standards is required as expeditiously as possible.
The district's variance hearing board is separate from the district's governing board.
It is the hearing board's responsibility to ensure that all deliberations concerning the grant of a variance are done in an open forum.
www.arb.ca.gov /enf/variance/variance.htm   (427 words)

  
 Variable Weights and Variance Explained
Variables with large weights tend to have larger loadings on the first component and smaller residual correlations than variables with small weights.
The usual method for computing variance accounted for by a factor is to take the sum of squares of the corresponding column of the factor pattern, yielding an unweighted result.
If the square of each loading is multiplied by the weight of the variable before the sum is taken, the result is the weighted variance explained, which is equal to the corresponding eigenvalue except in image analysis.
www.asu.edu /it/fyi/dst/helpdocs/statistics/sas/sasdoc/sashtml/stat/chap26/sect20.htm   (516 words)

  
 Standard Deviation and Variance: Common Measures of Variability
The variance and the closely-related standard deviation are measures of how spread out a distribution is. In other words, they are measures of variability.
The variance is computed as the average squared deviation of each number from its mean.
The formula (in summation notation) for the variance in a population is
davidmlane.com /hyperstat/A16252.html   (305 words)

  
 Variance (DSP Blockset)
The Variance block computes the variance of each column in the input, or tracks the variance of a sequence of inputs over a period of time.
The frame status of the output is the same as that of the input.
When the Running variance check box is selected, the block tracks the variance of each channel in a time-sequence of M-by-N inputs.
www.mathworks.com /access/helpdesk_r13/help/toolbox/dspblks/variance.html   (666 words)

  
 How Does Unequal Cost Path Load Balancing (Variance) Work in IGRP and EIGRP? - Cisco Systems
In general, load balancing is the capability of a router to distribute traffic over all the router network ports that are the same distance from the destination address.
Use the variance n command in order to instruct the router to include routes with a metric of less than n times the minimum metric route for that destination.
Also, the reported distance of neighbor D is 25, which is greater than the feasible distance (FD) of 20 through C. This means that, even if variance is set to 3, the E-D-A path is not selected for load balancing because Router D is not a feasible successor.
www.cisco.com /en/US/tech/tk365/technologies_tech_note09186a008009437d.shtml   (1176 words)

  
 Homogeneity of Variance in One-Way Models
One of the usual assumptions for the GLM procedure is that the underlying errors are all uncorrelated with homogeneous variances.
An approach that leads to tests that are much more robust to the underlying distribution is to transform the original values of the dependent variable to derive a dispersion variable and then to perform analysis of variance on this variable.
Unless the group variances are extremely different or the number of groups is large, the usual ANOVA test is relatively robust when the groups are all about the same size.
www.asu.edu /it/fyi/dst/helpdocs/statistics/sas/sasdoc/sashtml/stat/chap30/sect37.htm   (592 words)

  
 Cosmic Variance
Andrew Sullivan and Kevin Drum both link to this Pew Report on various worldwide opinions.
Perhaps there is a phase transition that countries undergo when their per capita GDP hits around 10,000.
Or, even more likely, there is some hidden third variable that is highly correlated with both GDP and religiosity.
www.cosmicvariance.com   (3271 words)

  
 Global Warming, Precession of the Equinox, Orbital Variance Theory
The variance is the cause of the Precession of the Equinox and is measured by (
The "Orbital Variance Theory" postulates that the Earth's orbit fluctuates over vast expanses of time (ages) and varies (in a precise path) from the outside of the orbital "ecliptic" (track) to the inside of the orbital "ecliptic"...like the runner mentioned above.
In the year 1900 the length of a year was measured at 31,556,926 seconds long and the length of a year has been gradually ("microscopically") decreasing since, and as a result, the globe has been warming up as she slowly moves closer to the Sun as her orbit shrinks.
www.aloha.net /~johnboy/orbitalV.htg/variance.htm   (2437 words)

  
 Wideman Comparative Glossary of Project Management Terms v3.1
A variable by itself contains no data or program logic; it must be connected such that it receives run-time identity from a bean elsewhere in the application.
Variances occur when you set a baseline plan and begin entering actual information into your schedule or cost spreadsheet.
The amount of a variance which will require a formal problem analysis report, as agreed to by the contractor and the customer.
www.maxwideman.com /pmglossary/PMG_V00.htm   (1668 words)

  
 The Variance
Prior to the public hearing on the proposed variance, the city or county must evaluate the proposal to determine whether or not it may have a significant adverse effect on the environment.
Prior to approval of a variance under Section 65852.1 the city or county must find that the resident or residents meet the age criteria, and that the floor area of the proposed unit does not exceed that allowed by the statute.
A variance allowing a 96-space mobilehome park on 28 acres in a mountainous area that was zoned for single residences on 1-acre minimum lots was overturned because the county's findings only described the subject property and not the conditions which distinguished it from surrounding properties (Topanga Assn.
ceres.ca.gov /planning/var/variance.htm   (3794 words)

  
 Statistics Glossary - random variables and probability distributions   (Site not responding. Last check: )
The (population) variance of a random variable is a non-negative number which gives an idea of how widely spread the values of the random variable are likely to be; the larger the variance, the more scattered the observations on average.
Examples of discrete random variables include the number of children in a family, the Friday night attendance at a cinema, the number of patients in a doctor's surgery, the number of defective light bulbs in a box of ten.
Typically, a Geometric random variable is the number of trials required to obtain the first failure, for example, the number of tosses of a coin untill the first 'tail' is obtained, or a process where components from a production line are tested, in turn, until the first defective item is found.
www.stats.gla.ac.uk /steps/glossary/probability_distributions.html   (2101 words)

  
 EPA Revision of Existing Variance and Exemption Regulations To Comply With Requirements of the Safe Drinking Water Act
Variances generally allow a system to provide drinking water that may be above the maximum contaminant level on the condition that the quality of the drinking water is still protective of public health.
Pursuant to section 1412(b)(15)(A) of the Act, variance technologies may not suffice to achieve compliance with the relevant maximum contaminant level or treatment technique, but the variance technologies must achieve the maximum reduction or inactivation efficiency that is affordable considering the size of the system and the quality of the source water.
A small system variance under this subpart may only be issued by either: (a) A State that is exercising primary enforcement responsibility under Subpart B for public water systems under the State's jurisdiction; or (b) The Administrator, for a public water system in a State which does not have primary enforcement responsibility.
www.epa.gov /OGWDW/standard/v&e-frn.html   (13545 words)

  
 Variance Components and Mixed Model ANOVA/ANCOVA
The variation in the levels of random factors is assumed to be representative of the variation of the whole population of possible levels.
The basic goal of variance component estimation is to estimate the population covariation between random factors and the dependent variable.
For ANOVA methods for estimating variance components, a solution is found for the system of equations relating the estimated population variances and covariances among the random factors to the estimated population covariances between the random factors and the dependent variable.
www.statsoft.com /textbook/stvarcom.html   (2537 words)

  
 Introduction to Quantitative Genetics
The CLT states that the sum of a large number of independent variables is distributed approximately by a normal distribution.
and the variance of a sum of independent values is the sum of the variances of those values.
Variance components consist of the same terms that make up the mean
www.zoology.ubc.ca /~whitlock/QGPG/QG1/Lecture.html   (833 words)

  
 The Magical Number Seven   (Site not responding. Last check: )
Variance is always stated in terms of the unit of measurement -- inches, pounds, volts, etc. -- whereas the amount of information is a dimensionless quantity.
The similarity of variance and amount of information might be explained this way: When we have a large variance, we are very ignorant about what is going to happen.
Eriksen [5] reports that, when size, brightness, and hue all vary together in perfect correlation, the transmitted information is 4.1 bits as compared with an average of about 2.7 bits when these attributes are varied one at a time.
www.well.com /user/smalin/miller.html   (8463 words)

  
 Poker Dictionary - Mike Caro University Poker Strategy
The greater the variance, the wilder the swings; the lower the variance, the more likely a given session results will be close to one's average result.
In mathematical terms, variance is the square of the standard deviation, a topic beyond the scope of this dictionary.
An example of a high variance play is raising on the last round of betting with a pure bluff in the hopes of getting a player who appears to be betting a weak hand to fold.
www.poker1.com /mcu/pokerdictionary/mculib_dictionary_v.asp   (715 words)

  
 RFC 1871 (rfc1871) - Addendum to RFC 1602 -- Variance Procedure
In determining whether to approve a variance, the IESG has discretion to limit the scope of the variance to particular parts of section 5 and to impose such additional restrictions or limitations as it determines appropriate to protect the interests of the Internet community.
The IESG may approve such a variance, however, only if it first determines that the likely benefits to the Internet community from entering or advancing the specification on the standards track are likely to outweigh the costs to the Internet community that result from noncompliance with section 5 of RFC 1602.
In determining whether to approve a variance, the IESG has discretion to limit the scope of the variance to particular parts of section 5 of RFC 1602 and to impose such additional restrictions or limitations as it determines appropriate to protect the interests of the Internet community.
www.faqs.org /rfcs/rfc1871.html   (914 words)

  
 Analysis of variance Info - Encyclopedia WikiWhat.com   (Site not responding. Last check: )
In statistics, analysis of variance (ANOVA) is a collection of statistical models and their associated procedures which compare means by splitting the overall observed variance into different parts.
The initial techniques of the analysis of variance were pioneered by the statistician and geneticist Ronald Fisher in the 1920s and 1930s.
The fixed effects model of analysis of variance applies to situations in which the experimenter has subjected his experimental material to several treatments, each of which affects only the mean of the underlying normal distribution of the response variable.
www.wikiwhat.com /encyclopedia/a/an/analysis_of_variance.html   (369 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.