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

Topic: Squared deviations


    Note: these results are not from the primary (high quality) database.


In the News (Fri 1 Jan 10)

  
 Root Sum Squared -
The sum of squared deviations is: 9 + 1 + 1...
and the hypotenuse is the square root of the sum of 1 squared + z squared.
if we want to calculate the squared root of the last value we can use...
root.faasv.com /index.php?k=root-sum-squared   (1083 words)

  
 Session 5, Part E: Measuring Variation
The mean of the squared deviations is 38 / 9 = 4 2/9, or approximately 4.22.
The variance is the mean of the squared deviations, so you could also say that it represents the average of the squared deviations.
Compare the standard deviation to the MAD of Line Plot B you found in Problem E2 and to the standard deviation of Line Plot A. Remember that in these problems, the mean is 5.
www.learner.org /channel/courses/learningmath/data/session5/part_e/variance.html   (799 words)

  
 ch4prob.html
SS cannot be less than zero because it is computed by adding squared deviations.
Squared deviations are always greater than or equal to zero.
You obtain exactly the same values (mean, deviations, and SS) whether the scores are a sample or a population.
www.unl.edu /tcweb/Faculty/ansorge/ch4prob.html   (446 words)

  
 BS 2.09 Quantitative Methods in Biological and Environmental Science
The variance in a normally distributed population is described by the average of N squared deviations from the mean.
Since dispersion is measured in squared deviations from the mean, it can be partitioned between sources, permitting the testing of statistical models.
It is then a property of the normal distribution that 95% of observations will lie within 1.960 standard deviations of the mean, and 99% within 2.576∙
www.soton.ac.uk /~cpd/mean2.html   (754 words)

  
 glosl.html
For example, in many traditional general linear model techniques, the loss function (commonly known as least squares) is the sum of squared deviations from the fitted line or plane.
In the most general terms, least squares estimation is aimed at minimizing the sum of squared deviations of the observed values for the dependent variable from those predicted by the model.
Lambda is defined as the geometric sum of 1 minus the squared canonical correlation, where lambda is Wilk's lambda.
www.statsoft.com /textbook/glosl.html   (4798 words)

  
 III_sec5.doc
The standard deviation (denoted by stdev) is almost the square root of the mean (average) of those squared deviations.
Standard Deviation: The best general measure of typical deviation is a special kind of average that is formed by adding the squares of the deviations, dividing by one less than the number of measurements, and then taking the square root of the quotient.
Round your deviations to two decimal places and make a frequency table and histogram of all the deviations from the mean.
www.austin.cc.tx.us /mparker/1333/fall04/III_sec5.doc   (2242 words)

  
 Chebyshev's Inequality
Okay, actually the square root of the average squared distance from the mean.
Since each standard deviation is 2, 6 standard deviations would be 12, 7 standard deviations would be 14, so 13 is 6 and a half standard deviations (or I could just break 13 into groups of 2 by doing 13/2, so 6.5).
So for group A, to be at least 120 means they are at least 8 away from the mean, so four standard deviations.
www.nova.edu /~hammack/stat/numstat/d1.html   (2242 words)

  
 Abstract Display
A lesser known statistic, average deviation, is similar but involves taking the absolute values of the deviations from the mean (absolute deviations) rather than the squared deviations from the mean.
It is not surprising that over repeated iterations, these absolute deviations become smaller and eventually go to zero.
We show that the total deviation of a set of numbers is always near if not equal to the largest absolute deviation (the difference between the mean and most extreme initial value).
src.truman.edu /browse_2003/display.php?abs_id=220   (2242 words)

  
 Measures of Variability
The mean of the squared deviations is 1.5.
Using the mean as the measure of the middle of the distribution, the variance is defined as the average squared difference of the scores from the mean.
The standard deviation is an especially useful measure of variability when the distribution is normal or approximately normal (see Probability) because the proportion of the distribution within a given number of standard deviations from the mean can be calculated.
cnx.rice.edu /content/m10947/latest   (977 words)

  
 Subgroup Regression Using Indicator Variables
Here I use the notation of the analysis of variance, where SST is the sum of squared deviations of the Y values from their mean, and SSE is the sum of squared deviations of the Y values from the values predicted by the model.
Define two indicator variables that will indicate membership in the latter two groups: s is 1 if a child is in the Strat class and 0 otherwise; d is 1 if a child is in the DRTA class and 0 otherwise.
Usually at least on of the categorical variables will be the causal variable of interest, and we are primarily interested in its effect on Y conditional on the other variables.
www.people.vcu.edu /~nhenry/Dummies.htm   (3719 words)

  
 GARCH Models and the Stochastic Process Underlying Exchange Rate Price Changes
For the ARCH model, the conditional variance changes over time as a function of past squared deviations from the mean.
The GARCH processes variance changes over time as a function of past squared deviations from the mean and past variances.
In their original form, a normal distribution is assumed, with a conditional variance that changes over time.
www.studyfinance.com /jfsd/htmlfiles/v13n2/johnston.html   (3719 words)

  
 Microsoft Excel : Standard Deviation
In this case, the 1 is NOT subtracted and the denominator for dividing the sum of squared deviations is simply N itself, the number of observations
The denominator for dividing the sum of squared deviations is N-1, where N is the number of observations
The standard deviation of the monthly temperatures evaluated for cities closer to the coast is lower and, therefore, an indication that those values tend to be more consistant.
www.beyondtechnology.com /tips016.shtml   (1072 words)

  
 Summer2001ObjectivesUnit4.htm
The variance is the mean of the squared deviations from the mean (sum of squares).
In statistics, "sum of squares" usually refers to the sum of the squared deviations of scores from the mean.
Deviation formulas are easier to understand (it is easy to see that distance from the mean is the basic unit of analysis) but they are not as good for computational purposes due to rounding errors.
www.andrews.edu /~thayerj/EDRM611/Summer2001ObjectivesUnit4.htm   (1852 words)

  
 Repeated Trials and Expected Values
Standard deviations, remember, are the square root of the average of the squared deviations of observed scores from the mean.
The second part of this equation considers the average squared deviation from the mean expected in any given trial.
In statistics this is similar to the law of large numbers (as a sample drawn from a population gets so large as to be the population then the mean of the sample will have to be the mean of the population).
home.stat.ucla.edu /~cochran/stat10/winter/lectures/lect8.html   (1175 words)

  
 MABS 67
Statistics, a measure of the degree of scattering of a frequency distribution about its arithmetic mean, equal to the square root of the mean of the squared deviations from the distribution mean.
Statistics, the average arithmetic mean of the deviations, taken without regard to sign, from some fixed value, usually the arithmetic mean of the data.
Statistics, the arithmetic average of the absolute values of the individual deviations in a distribution from a central value.
fog.ccsf.cc.ca.us /~gknapp/stddev.htm   (338 words)

  
 chi-squared tests
(This formula says: find how each x deviates from the mean µ, square each difference, add up all the squared-differences and divide by the standard deviation squared.) More general versions of this formula would allow different means and standard deviations for each measurement.
We could almost calculate the chi-squared, but we don't know the standard deviation for each count.
Never fear: most counts are distributed according to the Poisson distribution, and as such the standard deviation equals the square root of the expected count.
www.physics.csbsju.edu /stats/chi-square.html   (414 words)

  
 why_var2.doc
If one calculates variances instead of deviations, using SS/n (SS=sums of squared deviations, n=2), the average of the 36 sample values comes to 1.458, also an underestimate of the true value of 2.917, i.e.
Thus the sample deviations yields an underestimate of the true value of the population deviation of 1.5.
Now find the mean absolute deviation within each sample of the individual dice values around their sample mean.
exploringdata.cqu.edu.au /docs/why_var2.doc   (414 words)

  
 Dispersion - Frequency - Unit 5: Quantitative Techniques for Business - HNC Business
the sum of the squared deviations is 10
we can overcome the problems of "negative deviations" by squaring the deviations, because when two negative numbers are multiplied together the result is a postive number.
using the previous example, the standard deviation is the square root of 2 which is equal to 1.41 (two decimal places).
www.hnc-business.co.uk /les06_unit5.htm   (414 words)

  
 solver.doc
You put your best-guess values for the slope and intercept in C2 and D2, then create a column of YCALC and then the deviations squared, using the data in column A as the x-data points, the data in col. B as the y values (y data).
I (t) = I0 e- a t + B The purpose of Solver (in Excel) is to "iterate" toward a "solution" that will minimize the deviations between our data points and the value of the points calculated from our function using the trial values of a, B, and I0.
It’s straightforward BECAUSE the function is a linear combination of the separate functions x3 and x7, not the function itself is a straight line.
pirate.shu.edu /~ashworha/1815/solver.doc   (530 words)

  
 content
The mean of the distribution is 13.155, but if we discard the outlier the mean drops to 12.882, and the standard deviations with and without the outlier are 10.923 and 9.793, respectively.
It is the square root of the variance, which is the sum of squared distances between each datum and the mean, divided by the sample size minus one.
It is the mean squared deviation between each datum and its mean.
eksl-www.cs.umass.edu /eis/pages/techniques/dispersion-desc.html   (379 words)

  
 PCMDI Report 55
We compare liner trends based on minimization of absolte deviations (LA) and minimization of squared deviations (LS).
Trend fitting by the LA method can degrade the lower-tropospheric trend agreenebt of 0.03ºC/decade (over 1979-1996) previously reported for the MSU and radiosonde data.
This paper examines trend uncertainties in layer-average free atmosphere temperatures arising from the use of different trend estimation methods.
www-pcmdi.llnl.gov /publications/ab59.html   (358 words)

  
 Nonlinear Estimation
In the most general terms, least squares estimation is aimed at minimizing the sum of squared deviations of the observed values for the dependent variable from those predicted by the model.
Therefore, we can say that the goal of least squares estimation is to minimize a loss function; specifically, this loss function is defined as the sum of the squared deviation about the predicted values (the term loss was first used by Wald, 1939).
Ordinary least squares techniques assume that the residual variance around the regression line is the same across all values of the independent variable(s).
www.statsoft.com /textbook/stnonlin.html   (358 words)

  
 Shick - Standard Deviation
Two standard deviations away from the average (the red and green areas) account for roughly 95 percent of their games.
And three standard deviations (the red, green and blue areas) account for about 99 percent of their games.
is the square root of the average squared deviation from the mean.
www.footballguys.com /shickstandard_1.htm   (1783 words)

  
 Lecture Notes 3
For example, the sum of the deviations of the numbers in a set of data from the mean is zero, and the sum of the squared deviations of the numbers in a set of data from the mean is minimum value.
The standard deviation is the square root of 11.5 which is equal to 3.4 inches (expressed in same units as the raw data).
Even though the mean is sensitive to extreme values (i.e., extremely large or small data can cause the mean to be pulled toward the extreme data) it is still the most widely used measure of location.
business.clayton.edu /arjomand/business/l3.html   (1973 words)

  
 Lecture 11- Measures of Dispersion
For mathematical reasons, statistical procedures are based on measures of dispersion that use SQUARED deviations from the mean rather than absolute deviations.
Dispersion or "variation" in observations is what we seek to explain.
This is not enough, and we'll discuss several statistics used to measure variation, which differ in their importance.
www.janda.org /c10/Lectures/topic03/L11-dispersion/L11-Dispersion.html   (1473 words)

  
 tailor.html
In the case of the semivariance, the below-target deviations are squared.
The variable n is the degree to which deviations below the target return are raised.
The purpose of this paper is to show that an investor can control the skewness of a portfolio through the choice of a risk measure and that the appropriate level of risk aversion depends on the frequency of revising the portfolio.
www.handholders.com /old/tailor.html   (2978 words)

  
 Inter-Egg Correlation
The predictions for the GCP are for non-directional deviations of the means from expectation, and most of the individual event analyses use a Chisquare test, where Chisquare is composed of the squared, normalized meanshifts.
An alternative to the prediction-based analysis of the EGG data is based on the reasonable assumption that if an effect results in deviations at a specified time, there should be some non-zero level of correlation between the eggs at that time.
If one ignores the last two levels, which have too few data to give a reasonable estimate, the Z is 1.521 (1.711 without the 11% correction).
noosphere.princeton.edu /corr.v1.html   (1760 words)

  
 Curve Fitting and The Method of Least Squares
The sum of squared derivations is minimized by derivating this sum S and equalizing it to zero (that is a simple mathematical rule not to be proved here).
This is equivalent to replacing vertical deviations in the definition of least square curve by horizontal deviations.
It is possible to define another least square curve by considering perpendicular distances from each of the data points to the curve instead of either vertical or horizontal distances.
www.angelfire.com /ak4/neurope/ls.html   (2367 words)

  
 chi-squared tests
(This formula says: find how each x deviates from the mean µ, square each difference, add up all the squared-differences and divide by the standard deviation squared.) More general versions of this formula would allow different means and standard deviations for each measurement.
Never fear: most counts are distributed according to the Poisson distribution, and as such the standard deviation equals the square root of the expected count.
Finally it should be noted that the technical differences between a Poisson distribution and a normal distribution cause problems for small E
www.physics.csbsju.edu /stats/chi-square.html   (414 words)

  
 RESEARCH METHODS HANDBOOK
It has two properties: 1) the sum of the deviations of the individual scores (Xi) from the mean is zero, 2) the sum of squared deviations from the mean is smaller than what can be obtained from any other value created to represent the central tendency of the distribution.
It is especially useful as a measure of central tendency when there are very extreme scores in the distribution, such as would be the case if we had someone in the age distribution provided below who was 120.
The mean is the most often used measure of central tendency.
www.acastat.com /Handbook/5.html   (345 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.