Merge to Estimator date May 2010 In statistics , pointestimation involves the use of statistical sample sample data to calculate a single value known as a statistic which is to serve as a best guess or best estimate of an unknown fixed or random population parameter . More formally, it is the application of a point estimator to the data. In general, pointestimation should be contrasted with interval estimation such interval estimates are typically either confidence interval s in the case of frequentist inference , or credible intervals in the case of Bayesian inference . Point estimators minimum variance unbiased estimator minimum variance mean unbiased estimator MVUE , minimizes the risk function risk expected loss of the squared error loss function loss function . best linear unbiased estimator BLUE minimum mean squared error MMSE median unbiased estimator , minimizes the risk of the absolute error loss function maximum likelihood ML method of moments statistics method of moments , generalized method of moments Bayesian pointestimation Bayesian inference is based on the posterior distribution . Many Bayesian point estimators are the posterior distribution s statistics of central tendency , e.g., its mean, median, or mode Posterior mean , which minimizes the posterior risk function risk expected loss for a squared error loss function in Bayesian estimation, the risk is defined in terms of the posterior distribution. Posterior median , which minimizes the posterior risk for the absolute value loss function. maximum a posteriori MAP , which finds a maximum of the posterior ... of PointEstimation, 2nd ed year 1998 publisher Springer isbn 0 387 98502 6 ref ref name LeCam Special ... Hypotheses year 1959 cite book author Erich Leo Lehmann Lehmann, Erich title Theory of PointEstimation ... Markov chain Monte Carlo MCMC Properties of point estimates bias of an estimator Cram r Rao bound ... Estimation, Testing, and Selection year 2008 publisher Springer Category Estimation theory Category ... more details
The three pointestimation technique is used in management and information systems applications for the construction of an approximate probability distribution representing the outcome of future events, based on very limited information. While the distribution used for the approximation might be a normal distribution , this is not always so and, for example a triangular distribution might be used, depending on the application., ref name MOD2007 Ministry of Defence 2007 http www.aof.mod.uk aofcontent tactical risk downloads 3pepracgude.pdf Three point estimates and quantitative risk analysis http www.aof.mod.uk aofcontent tactical risk content tpe.htm Policy, information and guidance on the Risk Management aspects of UK MOD Defence Acquisition ref In three pointestimation, three figures are produced initially for every distribution that is required, based on prior experience or best guesses a the best case estimate m the most likely estimate b the worst case estimate. These are then combined to yield either a full probability distribution, for later combination with distributions obtained similarly for other variables, or summary descriptors of the distribution, such as the mean , standard deviation or percentile percentage points of the distribution. The accuracy attributed to the results derived can be no better than the accuracy inherent in the 3 initial points, and there are clear dangers in using an assumed form for an underlying distribution that itself has little basis. Estimation Based on the assumption possibly unwarranted that a double triangular distribution governs ... Three Point Estimate Approximations from www.super business.net http www.4pm.com articles PERT program evaluation & review technique.pdf Risk and duration estimates 3 point estimating from www.4pm.com DEFAULTSORT Three PointEstimation Category Statistical approximations Category Informal estimation ... External links http www.visionarytools.com decision making 3 point estimating.htm It Takes Three to Make ... more details
Unreferenced date December 2009 Wiktionary Estimation is the calculation calculated approximation of a result which is usable even if input data may be incomplete or uncertainty uncertain . In statistics , estimation theory and estimator , for topics involving inferences about probability distributions forecasting and prediction , for estimation of yet to be observed quantities sample statistic used to estimate a population parameter , such as the sample mean, , for the population mean, , or the sample proportion for a population proportion In mathematics , approximation or estimation typically means finding upper bound upper or lower bounds of a quantity that cannot readily be computed precisely. In signal processing , see estimation theory for approximating an unobserved signal on the basis of an observed signal containing noise. In project management , see estimation project management for applications to project planning. In physics , a Fermi problem is one concerning estimation in problems which typically involve making justified guesses about quantities that seem impossible to compute given limited available information. See also Estimated sign Estimated sign Guesstimate Category Estimation theory cs Odhad de Sch tzung es Estimaci n ko it Stima hu Becsl s ml pl Szacowanie simple Estimation sr th ... more details
In statistics , interval estimation is the use of Sampling statistics sample data to calculate an interval mathematics interval of possible or probable values of an unknown population parameter , in contrast to pointestimation , which is a single number. Neyman 1937 identified interval estimationestimation by interval as distinct from pointestimationestimation by unique estimate . In doing so, he recognised that then recent work quoting results in the form of an estimator estimate plus or minus a standard deviation indicated that interval estimation was actually the problem statisticians really had in mind. The most prevalent forms of interval estimation are confidence interval s a frequentism frequentist method and credible interval s a Bayesian probability Bayesian method . Other common approaches to interval estimation, which are encompassed by statistical theory, are Tolerance interval s Prediction interval s used mainly in Regression Analysis Likelihood function Relative likelihood Likelihood intervals There is a third approach to statistical inference , namely fiducial inference , that also considers interval estimation. Non statistical methods that can lead to interval estimates include fuzzy logic . An interval estimate is one type of outcome of a statistical analysis. Some other types of outcome are Pointestimationpoint estimates and Decision Theory decisions . Discussion see also Tolerance interval Relation to other intervals Confidence interval Alternatives and critiques ... associated with interval estimation may be summarised as follows When interval estimates are reported ... of testing the performance of interval estimation procedures. This arises because many such procedures ... the differences between the frequentist and Bayesian approaches to interval estimation. References Jerzy ... 3E2.0.CO 3B2 6 Outline of a Theory of Statistical Estimation Based on the Classical Theory of Probability ... the Behrens Fisher problem. Statistics DEFAULTSORT Interval Estimation Category Estimation ... more details
Regression estimation is a technique used to replace missing values in data . The variable with missing data is treated as the dependent variable, while the rest of the cases are treated as independent variables. A regression equation is then generated which can be used to predict missing values. This method reduces the variance associated with other techniques. Finding Regression Estimations To better understand what regression estimation is, one must become familiar with the process of finding the regression estimation. The first steps for finding regression estimations are to collect bivariate data and plot it on a scatter plot . The scatter plot should have a linear correlation , in order to have a regression estimation. By having a linear correlation, one can then draw a line of best fit or regression line. Once these steps are complete, one can predict missing values regression estimations by using the regression equation. The regression equation describes the line of best fit and is defined as Y a bX, where Y is the value that one is trying to predict, X is the value that one is given, a is the point where the regression line crosses the y axis of the scatter plot, and b represents the slope of the regression line Caldwell, 2007 . Most may better recognized this equation as slope intercept form . Finally, to find the regression estimation, plug a, b, and X into the regression equation and solve for Y . See also Imputation statistics References Tabachnick, B. G., & Fidel, L. S. 2001 . Using multivariate statistics 4th ed. . Boston, Mass. Allyn and Bacon. Caldwell, S. 2007 . Statistics unplugged 2nd Ed. . Belmont, CA. Thomas Wadsworth. Category Missing data statistics stub ... more details
Structural estimation is a technnique for estimating deep structural parameter Statistics and econometrics parameter s of theoretical model economics economic models . In this sense, structural estimation is contrasted with reduced form estimation, which generally provides evidence about partial equilibrium relationships in a regression analysis regression framework. Specific structural estimation techniques include generalized method of moments and maximum likelihood . Structural estimation is used by economist s, econometrician s, and statistician s. Category Economics models Econometrics stub ... more details
In probability and statistics , density estimation is the construction of an estimate, based on observed data , of an unobservable underlying probability density function . The unobservable density function is thought of as the density according to which a large population is distributed the data are usually thought of as a random sample from that population. A variety of approaches to density estimation are used, including Parzen window s and a range of data clustering techniques, including vector quantization . The most basic form of density estimation is a rescaled histogram . Example of density estimation We will consider records of the incidence of diabetes . The following is quoted verbatim from the data set description A population of women who were at least 21 years old, of Pima Indian heritage and living near Phoenix, Arizona, was tested for diabetes according to World Health Organization criteria. The data were collected by the US National Institute of Diabetes and Digestive and Kidney Diseases. We used the 532 complete records. In this example, we construct three density estimates for glu Blood plasma plasma glucose concentration , one Conditional probability conditional .... That is, a Gaussian density function is placed at each data point, and the sum of the density ... glu . center See also Kernel density estimation Mean integrated squared error Histogram Multivariate kernel density estimation References Peter Hall, Jeffrey S. Racine and Qi Li. Cross Validation and the Estimation ... Press, 2007, ISBN 0691121613. See Chapter 1. D.W. Scott. Multivariate Density Estimation. Theory, Practice and Visualization . New York Wiley, 1992. B.W. Silverman. Density Estimation . London Chapman ... for free density estimation software packages http www.ruwpa.st and.ac.uk distance Distance 4 from ... dimensional density estimation http cran.r project.org web packages np index.html The np package ... libagf.sourceforge.net libAGF C software for variable kernel density estimation . Category Estimation ... more details
estimation Statistical signal processing Sufficiency statistics Wiener filter colend Notes reflist group note References reflist Reference list Theory of PointEstimation by E.L. Lehmann and G. Casella ...Estimation theory is a branch of statistics and signal processing that deals with estimating the values ... distributed, so that the transit time must be estimated. In estimation theory, it is assumed the measured ... signal . Without randomness, or noise, the problem would be determinism deterministic and estimation would not be needed. Estimation process The entire purpose of estimation theory is to arrive at an estimator ... and minimized for the MMSE estimator. Estimators Commonly used estimators and estimation ... At this point, these two estimators would appear to perform the same. However, the difference between ... of a uniform distribution main German tank problem One of the simplest non trivial examples of estimation is the estimation of the maximum of a uniform distribution. It is used as a hands on classroom exercise and to illustrate basic principles of estimation theory. Further, in the case of estimation ... , due to application of maximum estimation to estimates of German tank production during World War II .... This can be seen as a very simple case of maximum spacing estimation . The sample maximum is the maximum ... Numerous fields require the use of estimation theory. Some of these fields include but are by no means ... information from the data as possible. See also Category Estimation theory Category Estimation ... entropy spectral estimation Method of moments statistics Method of moments , generalized method ... Estimation Theory by Steven M. Kay ISBN 0 13 345711 7 An Introduction to Signal Detection and Estimation by H. Vincent Poor ISBN 0 387 94173 8 Detection, Estimation, and Modulation Theory, Part 1 by Harry L. Van Trees ISBN 0 471 09517 6 http gunston.gmu.edu demt demtp1 website Optimal State Estimation Kalman, H infinity, and Nonlinear Approaches by Dan Simon http academic.csuohio.edu simond estimation ... more details
In statistics , sequential estimation refers to estimation theory estimation methods in sequential analysis where the sample size is not fixed in advance. Instead, data is evaluated as it is collected, and further sampling is stopped in accordance with a pre defined stopping rule as soon as significant results are observed. See also Sequential Probability Ratio Test Testimator References Thomas S. Ferguson 1967 Mathematical statistics A decision theoretic approach. , Academic Press. ISBN 0122537505 Cite book authorlink Abraham Wald first Abraham last Wald title Sequential Analysis year 1947 publisher John Wiley and Sons location New York isbn 0471918067 quote See Dover reprint ISBN 0486439127 stats stub Category Estimation theory Category Sequential methods pl Estymacja sekwencyjna ... more details
The simplest and most common approach uses histogram based estimation, but other approaches have been ... references Entropy 20estimation.pdf Nonparametric entropy estimation An overview . In International ... T. Sch rmann, Bias analysis in entropy estimation. In J. Phys. A Math. Gen , 37 2004 , pp. L295 ... point in our dataset, we can find the distance to its nearest neighbour . We can in fact estimate the entropy ... a prior on the distribution can help the estimation. One such Bayesian estimator was proposed in the neuroscience ... distribution . References reflist DEFAULTSORT Entropy Estimation Category Entropy and information ... more details
This article is about the technique in signal processing. The term frequency estimation can also refer to Kernel density estimation probability estimation . Frequency estimation is the process of Estimation theory estimating the complex frequency components of a Digital signal processing signal in the presence of noise ref Hayes, Monson H., Statistical Digital Signal Processing and Modeling , John Wiley & Sons, Inc., 1996. ISBN 0 471 59431 8. ref . The most common methods involve identifying the noise Linear subspace subspace to extract these components. The most popular methods of noise subspace based frequency estimation are Pisarenko harmonic decomposition Pisarenko s Method , Multiple signal classification MUSIC , the eigenvector solution, and the minimum norm solution. For example, consider a signal, math x n math , consisting of a sum of math p math complex exponentials in the presence of white noise , math w n math . This may be represented as math x n sum i 1 p A i e j n omega i w n math . Thus, the power spectrum of math x n math consists of math p math impulses in addition to the power due to noise. The noise subspace methods of frequency estimation are based on Eigendecomposition eigen decomposition of the autocorrelation matrix into a signal subspace and a noise subspace. After these subspaces are identified, a frequency estimation function is used to find the component frequencies from the noise subspace. Methods of frequency estimation Expert subject date April 2009 Pisarenko harmonic decomposition Pisarenko s Method math hat P PHD e j omega frac 1 mathbf e H mathbf v min 2 math Multiple signal classification MUSIC math hat P MU e j omega frac 1 sum i p 1 M mathbf e H mathbf v i 2 math , Eigenvector Method math hat P EV e j omega frac 1 sum i p 1 M frac 1 lambda i mathbf e H mathbf v i 2 math Minimum Norm math hat P MN e j omega frac 1 mathbf e H mathbf a 2 ... DEFAULTSORT Frequency Estimation Category Digital signal processing ... more details
Trend estimation is a statistics statistical technique to aid interpretation of data. When a series of measurements of a process are treated as a time series , trend estimation can be used to make and justify statements about tendencies in the data. By using trend estimation it is possible to construct a model which is independent of anything known about the nature of the process of an incompletely understood system for example, physical, economic, or other system . This model can then be used to describe the behaviour of the observed data. In particular, it may be useful to determine if measurements exhibit an increasing or decreasing trend which is statistically distinguished from randomness random behaviour . Some examples are determining the trend of the daily average temperatures at a given location, from winter to summer or the trend in a global temperature series over the last 100 years. In the latter case, issues of homogeneity statistics homogeneity are important for example, about whether the series is equally reliable throughout its length . Fitting a trend least squares Given a set of data and the desire to produce some kind of model of those data model, in this case, meaning a function fitted through the data , there are a variety of functions that can be chosen for the fit ... squares fitting, by weighting each point by the inverse of the variance of that point. In most ..., leading to a search for alternative approaches to avoid its use in model estimation. One ... over one unit of time. Strictly speaking, that interpretation is applicable for the estimation ... of the trend plus noise, with the noise at each data point being independent and identically distributed ... influences , the use of least squares estimation of the trend is not valid. Also where the variations ... M., Hollingsworth D. 1999 , A comparison of methods for trend estimation , Applied Economics Letters ... in Memory of Alfred Nobel . DEFAULTSORT Trend Estimation Category Estimation theory Category Time ... more details
Motion estimation is the process of determining motion vector s that describe the transformation from one 2D image to another usually from adjacent video frame frames in a video sequence. It is an ill posed problem as the motion is in three dimensions but the images are a projection of the 3D scene onto a 2D plane. The motion vectors may relate to the whole image global motion estimation or specific parts, such as rectangular blocks, arbitrary shaped patches or even per pixel . The motion vectors may be represented by a translational model or many other models that can approximate the motion of a real video camera, such as rotation and translation in all three dimensions and zoom. Closely related to motion estimation is optical flow , where the vectors correspond to the perceived movement of pixels. In motion estimation an exact 1 1 correspondence of pixel positions is not a requirement. Applying the motion vectors to an image to synthesize the transformation to the next image is called motion compensation . The combination of motion estimation and motion compensation is a key part of video compression as used by MPEG 1, 2 and 4 as well as many other video codecs . Algorithms The methods for finding motion vectors can be categorised into pixel based methods direct and feature based methods indirect . A famous debate resulted in two papers from the opposing factions being produced to try to establish a conclusion. ref Philip H.S. Torr and Andrew Zisserman Feature Based Methods for Structure and Motion Estimation, ICCV Workshop on Vision Algorithms, pages 278 294, 1999 ref ref Michal Irani and P. Anandan About Direct Methods, ICCV Workshop on Vision Algorithms, pages 267 277, 1999. ref Direct Methods Block matching algorithm Phase correlation and frequency domain methods Pixel recursive algorithms Maximum a posteriori MAP Markov network MRF type Bayesian estimators Optical ... Estimation theory ca Estimaci de moviment es Estimaci n de Movimiento fr Estimation de mouvement ... more details
Casualty estimation is the process of estimating the number of injuries or deaths in a battle or natural disaster that has already occurred. On the other, casualty prediction is the process of estimating the number of injuries or deaths that might occur in a planned or potential battle or natural disaster. Measures used to imply casualties include Reported number of kills Number of enemy individual weapons captured after engagement Number of tanks and aircraft lost Remote sensing of mass graves Methods MASINT Measures and Signals Intelligence alone cannot give a reasonable estimate of casualties. What Electro optical MASINT Spectroscopic MASINT Spectroscopic MASINT can do is help find mass graves. Geophysical MASINT can help localize metal and possibly bodies at that site. TECHINT is needed if there are weapons or artifacts to analyze. IMINT has a role to play in tracking movements. These all have to combine with all source analysis. Perhaps the losses of tanks and aircraft, if available, might better predict what actually happened in a battle. Electro optical MASINT Mass graves MASINT s mass graves capability is a means that has been used for remote sensing of clandestine mass graves. Author Sam Adams book, War of Numbers discusses, in great detail, a process of casualty estimation. Adams was a CIA analyst who eventually resigned over what he felt was political manipulation of casualty figures in the Vietnam War . He explains how he came up with casualty figures for the NLF and PAVN. Adams, and other U.S. analysts dealing with a guerilla war in jungle, found there were better metrics than body count . David Hackworth , for example, used number of enemy weapons captured after an engagement, and that turned out to be a good predictor of casualties, with certain limits. See also Body count Casualty prediction Loss Exchange Ratio References refs External links http ww2.csfs.ca CSFS Journal.aspx?ID 46&year 2006 Related article in Canadian Society of Forensic Science Journal ... more details
In discrete event simulation concurrent estimation is a technique used to estimate the effect of alternate parameter settings on a discrete event system. For example from observation of a computer simulated telecommunications system with a specified buffer size math B 0 math , one estimates what the performance would be if the buffer size had been set to the alternate values math B 1, ldots,B n math . Effectively the technique generates during a single simulation run math n math alternative histories for the system state variables, which have the same probability of occurring as the main simulated state path this results in a computational saving as compared to running math n math additional simulations, one for each alternative parameter value. The technique was developed by Cassandras, ref http vita.bu.edu cgc vita.bu.edu ref Strickland and Panayiotou. ref http www.eng.ucy.ac.cy christos vita.bu.edu ref References Reflist Refbegin cite book author Cassandras, C.G. coauthors Lafortune, S. year 2008 title Introduction to Discrete Event Systems publisher Springer isbn 0387333320 Refend Category Control theory Category Events computing ... more details
In mathematics, the estimation lemma gives an upper bound for a contour integral . If f is a complex number complex valued, continuous function on the contour math Gamma math and if its absolute value Complex numbers absolute value f z is bounded by a constant M for all z on math Gamma math , then math left int Gamma f z , dz right le M , l Gamma , math where math l Gamma math is the arc length of math Gamma math . In particular, we may take the maxima and minima maximum math M max z in Gamma f z math as upper bound. Intuitively, the lemma mathematics lemma is very simple to understand. If a contour is thought of as many smaller contour segments connected together, then there will be a maximum f z for each segment. Out of all the maximum f z s for the segments, there will be an overall largest one. Hence, if the overall largest f z is summed over the entire path then the integral of f z over the path must be less than or equal to it. The estimation lemma is most commonly used as part of the methods of contour integration with the intent to show that the integral over part of a contour goes to zero as math z math goes to infinity. An example of such a case is shown below. Example Image Upper halfcircle with i.svg thumb 200px The contour &Gamma . Problem. Find an upper bound for math biggl int Gamma frac 1 z 2 1 2 , dz biggr , math where math Gamma math is the upper half circle math z a math with radius math a 1 math traversed once in the counterclockwise direction. Solution. First observe that the length of the path of integration is half the circumference of a circle with radius a , hence math l Gamma frac 1 2 2 pi a pi a. math Next we seek an upper bound M for the integrand when math z a math . By the triangle inequality we see that math z 2 z 2 z 2 1 1 le z 2 1 1, math ... left frac 1 z 2 1 2 right le frac 1 a 2 1 2 . math Therefore we apply the estimation lemma with M 1 ... J.M., Complex Analysis Springer, 2003 . Category Complex analysis Category Lemmas fr Lemme d estimation ... more details
In applied statistics, optimal estimation is a regularization mathematics regularized matrix mathematics matrix inverse problem inverse method based on Bayes theorem . It is used very commonly in the geoscience s, particularly for atmospheric sounding . A matrix inverse problem looks like this math mathbf A vec x vec y math The essential concept is to transform the matrix, A , into a conditional probability and the variables, math vec x math and math vec y math into probability distributions by assuming Gaussian statistics and using empirically determined covariance matrices. Derivation Typically, one expects the statistics of most measurements to be normal distribution Gaussian . So for example for math P vec y vec x math , we can write math P vec y vec x frac 1 2 pi m n 2 boldsymbol S y exp left frac 1 2 boldsymbol A vec x vec y T boldsymbol S y 1 boldsymbol A vec x vec y right math where m and n are the numbers of elements in math vec x math and math vec y math respectively math boldsymbol A math is the matrix to be solved the linear or linearised forward model and math boldsymbol S y math is the covariance matrix of the vector math vec y math . This can be similarly done for math vec x math math P vec x frac 1 2 pi m 2 boldsymbol S x a exp left frac 1 2 vec x widehat x a T boldsymbol S x a 1 vec x widehat x a right math Here math P vec x math is taken to be the so called a priori distribution math widehat x a math denotes the a priori values for math vec x math while math boldsymbol S x a math is it s covariance matrix. The nice thing about the Gaussian distributions is that only two parameters are needed to describe them and so the whole problem can be converted once again to matrices. Assuming that math P vec x vec y math takes the following form math P vec x vec y frac 1 2 pi m n 2 boldsymbol S x exp left frac 1 2 vec x widehat x T boldsymbol S x 1 vec x widehat ... likelihood estimation. Typically with optimal estimation, in addition to the vector of retrieved ... more details
Estimation and Benchmarking Resource Centre ref Formal estimation model Function Point Analysis ..., SSU Software Size Unit , Story point s based estimation in Agile software development Group estimation ...Software development efforts estimation is the process of predicting the most realistic use of effort ... processes and bidding rounds. State of practice Published surveys on estimation practice suggest that expert estimation is the dominant strategy when estimating software development effort. ref cite web author J rgensen, M. title A Review of Studies on Expert Estimation of Software Development Effort ... effort overrun seems to be about 30 and not decreasing over time. For a review of effort estimation ... surveys on software effort estimation url http ieeexplore.ieee.org xpls abs all.jsp?arnumber 1237981 ref However, the measurement of estimation error is not unproblematic, see Assessing and interpreting ... estimation for software development projects since at least the 1960s see, e.g., work by Farr ref cite ... Nelson, E. A. 1966 . Management Handbook for the Estimation of Computer Programming Costs. AD A648750 ... effort estimation models. The early models were typically based on regression analysis or mathematically .... The perhaps most common estimation products today, e.g., the formal estimation models COCOMO and SLIM have their basis in estimation research conducted in the 1970s and 1980s. The estimation approaches ... Estimation Practices by Applying Use Case Models url http www.springerlink.com content 7lpyel912m5cr654 ref in the 1990s and http www.cosmicon.com COSMIC in the 2000s. Estimation approaches There are many ways of categorizing estimation approaches, see for example. ref Briand, L. C. and I. Wieczorek 2002 . Resource estimation in software engineering. Encyclopedia of software engineering. J. J. Marcinak ... A Systematic Review of Software Development Cost Estimation Studies url http simula.no research engineering publications Jorgensen.2007.1 ref The top level categories are the following Expert estimation ... more details
Parametric Estimation of Effort, Schedule, Cost, Risk. Mimimum time and staffing concepts based on Brooks ... ITK method CETIN See also Software development effort estimation Software metric Project management Cost overrun Risk Comparison of development estimation software External links http www.stellman greene.com ch03 Software Estimation chapter from http www.stellman greene.com Applied Software Project ... 2006 11 dynamics of effort estimation in most.html The Dynamics of Software Projects Estimation http www.construx.com Page.aspx?nid 297 Resources on Software Estimation from Steve McConnell http www.uduko.com topic detail details 47 Links on tools and techniques of software estimation Category Software ... Artigos UCP Banerjee UCP An Estimation Approach.pdf Definition of Use Case Points method ... Artigos UCP Clemmons Project Estimation with UCP.pdf Project Estimation With Use Case Points ... more details
merge Pose computer vision Pose Estimation discuss Talk 3D Pose Estimation Merger proposal date March 2010 3D pose estimation is the problem of determining the transformation of an object in a 2D image which gives the 3D object. The need for 3D pose estimation arises from the limitations of feature based pose estimation. There exist environments where it is difficult to extract corners or edges from an image. To circumvent these issues, the object is dealt with as a whole through the use of free form contours. ref cite web author Bodo Rosenhahn url http www.ks.informatik.uni kiel.de modules.php name Publikationen title Pose Estimation of 3D Free form Contours in Conformal Geometry publisher Institut fur Informatik und Praktische Mathematik, Christian Albrechts Universitat zu Kiel language English German accessdate 2008 06 09 archiveurl http web.archive.org web 20080603222942 http www.ks.informatik.uni ... 3D pose estimation from an uncalibrated 2D camera It is possible to estimate the 3D rotation and translation ... June 2010 DASHBot deadurl no ref 3D pose estimation from a calibrated 2D camera Given a 2D image of an object ... ROSENHAHN1 CVOnlinePose.html title Foundations about 2D 3D Pose Estimation publisher CV Online accessdate ... rays, can be determined. Pseudocode The algorithm for determining pose estimation is based on the Iterative Closest Point algorithm. The main idea is to determine the correspondences between 2D image ... br b Estimate the nearest point of each projection ray to a point on the 3D contour br c Estimate ... ray R br c For each 3D contour br c1 Estimate the nearest point P1 of ray R to a point on the contour br c2 if n 1 chose P1 as actual P for the point line correspondence br c3 else compare P1 with P ... camera calibration References reflist 2 Bibliography Rosenhahn, B. Foundations about 2D 3D Pose Estimation. Rosenhahn, B. Pose Estimation of 3D Free form Contours in Conformal Geometry. Athitsos, V ... as more information on 3D pose estimation Category Computer vision Category Geometry in computer vision ... more details
In statistics , adaptive or variable bandwidth kernel density estimation is a form of kernel density estimation in which the size of the kernels used in the estimate are varied depending upon either the location of the samples or the location of the test point. It is a particularly effective technique when the sample space is multi dimensional. ref name Terrell Scott1992 Cite journal author1 D. G. Terrell author2 D. W. Scott title Variable kernel density estimation journal Annals of Statistics volume 20 pages 1236&ndash 1265 year 1992 doi 10.1214 aos 1176348768 ref Rationale Given a set of samples, math lbrace vec x i rbrace math , we wish to estimate the density, math P vec x math , at a test point, math vec x math math P vec x approx frac W n math math W sum i 1 n w i math math w i K left frac vec x vec x i h right math where n is the number of samples, K is the Kernel statistics kernel and h is its width. The kernel can be thought of as a simple, linear filter . Using a fixed filter width may mean that in regions of low density, all samples will fall in the tails of the filter with very ... regions of the sample space. There are two methods of doing this balloon and pointwise estimation. In a balloon estimator, the kernel width is varied depending on the location of the test point ... to the density at the test point math h frac k left n P vec x right 1 D math where k is a constant ... Cite journal last Taylor first Charles title Classification and kernel density estimation journal Vistas ... where c sub i sub is the class of the i th sample. The class of the test point may be estimated through ... samples along with estimates of the gradients of R determine the class of a test point through a dot ... be extrapolated to the test point math R vec x approx tanh p , math ref name Mills2010 Two class classifications ... for multivariate, adaptive kernel density estimation. References references Category Classification algorithms Category Statistical classification Category Estimation of densities Category Non ... more details
For estimation in general, see Estimation . In project management i.e., for engineering , accurate estimates are the basis of sound project planning . Many processes have been developed to aid engineers in making accurate estimates, such as Analogy based estimation Compartmentalization engineering Compartmentalization i.e., breakdown of tasks Delphi method Documenting estimation results Educated assumptions Estimating each task Examining historical data Identifying dependencies Parametric estimating Risk assessment Structured planning Popular estimation processes for software projects include Cocomo Cosysmo Event chain methodology Function points Program Evaluation and Review Technique PERT Proxy Based Estimation PROBE from the Personal Software Process The Planning Game from Extreme Programming Weighted Micro Function Points WMFP Wideband Delphi See also Estimation in software engineering Software development effort estimation Comparison of development estimation software Cognitive bias Decision making Decision making software Work Breakdown Structure Project management List of project management software Software metric Wideband Delphi Guesstimate Ballpark estimate Construction Estimating Software External links Wiktionary http www.stellman greene.com aspm images ch03.pdf Estimation chapter from Applied Software Project Management PDF http softwaresurvival.blogspot.com 2006 11 dynamics of effort estimation in most.html The Dynamics of Software Projects Estimation http www.intaver.com Articles RP Art Estimations.html Estimations in project management Category Project management de Sch tzung fr Estimation gestion de projet hu Becsl s nl Schatten pl Szacowanie sr vi D to n qu n l d n ... more details
Articulated body pose estimation , in computer vision , is the study of algorithms and systems that recover the pose of an articulated body, which consists of joints and rigid parts using image based observations. It is one of longest lasting problems in computer vision because of the complexity of the models that relate observation with pose, and because of the variety of situations in which it would be useful. ref http citeseer.ist.psu.edu moeslund01survey.html Survey of Computer Vision Based Human Motion Capture 2001 ref ref http www.sciencedirect.com science article B6WCX 4M1DB7H 1 2 8da6f6e7a8c8e07d9331bc7738c6d499 Survey of Advances in Computer Vision based Human Motion Capture 2006 ref Description There is a need to develop accurate tether less, vision based articulated body pose estimation systems to recover the pose of bodies such as the human body, a hand, or non human creatures. Such a system have several foreseeable applications, including Marker less motion capture for human computer interfaces, Physiotherapy , 3D animation , Ergonomics studies, Robot control, and Visual surveillance. One of the major difficulties in recovering pose from images is the high number of degrees of freedom DOF in the body s movement that has to be recovered. Any rigid object requires six DOF to fully describe its pose, and each additional rigid object connected to it adds at least one DOF. A human body contains no less than 10 large body parts, equating to more than 20 DOF. This difficulty is compounded by the problem of self occlusion, where body parts wikt occlusion occlude each other depending on the configuration of the parts. Other challenges involve dealing with varying lighting ... computation time. The typical articulated body pose estimation system involves a model based ... surface point clouds, and 3D surface meshes. Related technology A commercially successful but specialized computer vision based articulated body 3D Pose Estimation pose estimation technique is optical ... more details
to the placement of the anchor point. ref Cite book author Silverman, B.W. title Density Estimation ... where no data are observed. In kernel density estimation, the contribution of each data point is smoothed out from a single point into a region of space surrounding it. Aggregating the individually ...mergeto Kernel density estimation date September 2010 Kernel density estimation is a nonparametric technique for density estimation i.e., estimation of probability density function s, which is one of the fundamental questions in statistics . It can be viewed as a generalisation of histogram density estimation ... first E. title On estimation of a probability density function and mode journal Annals of Mathematical ... density estimation has reached a level of maturity comparable to their univariate counterparts. ref ... the choice of an anchor point the lower left corner of the histogram grid . For the histogram on the left, we choose 1.5, 1.5 for the one on the right, we shift the anchor point by 0.125 ... are due to the change in the anchor point only. The colour coding indicates the number of data points ... Image Synthetic data 2D histograms.png thumb center 500px alt Left. Histogram with anchor point at 1.5, 1.5 . Right. Histogram with anchor point at 1.625, 1.625 . Both histograms have a bin ... point. Comparison of 2D histograms. Left. Histogram with anchor point at 1.5, 1.5 . Right. Histogram with anchor point at 1.625, 1.625 . Both histograms have a bin width of 0.5, so differences in appearances of the two histograms are due to the placement of the anchor point. One possible solution to this anchor point placement problem is to remove the histogram binning grid completely ... kernels. Right. Kernel density estimate. The goal of density estimation is to take a finite sample ... between multivariate kernel density estimation from its univariate analogue since orientation ... kernel density estimation journal Journal of the American Statistical Association year 1993 volume ... more details
Merge from Multivariate kernel density estimation date September 2010 File Kernel density.svg thumb right 250px Kernel density estimation of 100 normal distribution normally distributed random number generator random numbers using different smoothing bandwidths. In statistics , kernel density estimation KDE is a non parametric statistics non parametric way to density estimation estimate the probability density function of a random variable . Kernel density estimation is a fundamental data smoothing ... name Par1962 cite journal doi 10.1214 aoms 1177704472 last Parzen first E. title On estimation of a probability ... title Non parametric estimation of a multivariate probability density journal Theory of Probability ... of the data. In this case, we have 6 bins each of width 2. Whenever a data point falls inside this interval, we place a box of height 1 12. If more than one data point falls inside the same bin ... outside of density estimation. For example, in thermodynamics , this is equivalent to amount of heat ... x sub i sub . Similar methods are used to construct discrete Laplace operator s on point clouds ... 1994 title A comparative study of several smoothing methods in density estimation journal Computational ... 1996 title A brief survey of bandwidth selection for density estimation journal Journal of the American ... density estimation journal Journal of the Royal Statistical Society. Series B volume 53 issue ... series methods for density estimation url http projecteuclid.org euclid.aos 1176342997 ... kernel density estimation adaptive or variable bandwidth kernel density estimation . Practical estimation ... is ref name SI1998 Cite book author1 Silverman, B.W. title Density Estimation for Statistics and Data ... kernel density estimation . In CrimeStat , kernel density estimation is implemented using five different ... and dual kernel density estimate routines are available. Kernel density estimation is also used in interpolating ... , kernel density estimation is implemented by the code smooth kdensity code option, the datafile ... more details
Encyclopedia
top
