Observationalerror is the difference between a measurement measured value of quantity and its true value. ref name Dodge Dodge, Y. 2003 The Oxford Dictionary of Statistical Terms , OUP. ISBN 0 19 920613 9 ref In statistics , an error is not a mistake . Variability is an inherent part of things being measured and of the measurement process. Science and experiments When either random variable randomness or uncertainty modeled by probability theory is attributed to such errors, they are errors in the sense in which that term is used in statistics see errors and residuals in statistics . Every time we repeat a measurement with a sensitive instrument, we obtain slightly different results. The common statistical model we use is that the error has two additive parts systematic error which always occurs with the same value when we use the instrument in the same way, and random error which may vary from observation to observation. The systematic error is sometimes called statistical bias. It is controlled by very carefully standardized procedures. Part of the education in every science is how to use the standard instruments of the discipline. The random error or random variable random variation ... in quantum mechanics see Measurement in quantum mechanics . Random error often occurs when instruments ... error in their least significant digit. Three measurements of a single object might read something like 0.9111g, 0.9110g, and 0.9112g. Surveys The term observationalerror is also sometimes used to refer to response errors and some other types of non sampling error . ref name Dodge Dodge, Y. 2003 ... in statistics error in general Replication statistics statistical theory metrology test method Propagation of uncertainty Instrument error References references Errors of Measurement in Statistics ... 1267450 Category Error Category Measurement Category Uncertainty of numbers ar be x old ca Error experimental de Messabweichung el es Error experimental fr Erreur ... more details
An observational science is a science where it is not possible to construct controlled experiment s in the area under study. For example, in astronomy , it is not possible to create or manipulate stars or galaxies in order to observe what happens. Other examples of necessarily observational sciences include geology , paleontology , epidemiology , and much of the social sciences . Other fields of scientific study can have observational as well as experimental aspects. In high energy physics , for example, some interactions involving energies higher than can be created in any experiment can be observed indirectly through astronomical observations. To substitute for the inability to directly construct experiments as part of the scientific method , two main strategies are used. First, Multivariate statistics multivariate statistical techniques allow the approximation of experimental control with statistical control. Secondly, experimental observations of previously unobserved phenomena can be used to suggest new hypotheses and test existing ones. This can be seen as making use of pre existing natural experiments . In the social sciences , sociology and economics are generally held to be examples of observational sciences, because of the impracticality not to mention dubious ethical status of manipulating whole societies or economies for experimental purposes. However, microeconomics can be regarded as an experimental science, because it is possible to set up experimental micro economies. Sometimes fields of study can change from being observational to being experimental for example, until the early 21st century, the study of comets was entirely observational it became experimental when the first Deep Impact spacecraft man made cometary collision was engineered in 2005. See also Observational astronomy Experimental science External links http www.asa3.org archive evolution 199605 0063.html Is observational science a useful categorization? sci stub Category Scientific method ... more details
Merge from Natural experiment date September 2010 In statistics , an observational study draws inferences about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator. ref name urlObservational study Cite web url http www.medicine.ox.ac.uk bandolier booth glossary observ.html title Observational study work accessdate 2008 06 25 ref This is in contrast with experimental control controlled experiment s, such as randomized controlled trial s, where each subject is randomly assigned to a treated group or a control group before the start of the treatment. Reasons for uncontrolled experimentation The assignment of treatments may be beyond the control of the investigator for a variety of reasons A randomized experiment would violate ethics ethical standards. Suppose one wanted to investigate the abortion breast cancer hypothesis , which postulates a causal link between induced abortion .... In an observational study, the investigator would typically start with a treatment group consisting ... subject. An observational study would typically start with a group of symptomatic subjects and work ... of bias . A major challenge in conducting observational studies is to draw inferences that are acceptably ... by chance. In observational studies, investigators may use propensity score matching PSM in order ... the Reporting of Observational Studies in Epidemiology STROBE statement, in which they called for observational ... SJ , Peter C. G tzsche G tzsche PC , Vandenbroucke JP title The Strengthening the Reporting of Observational Studies in Epidemiology STROBE Statement Guidelines for Reporting Observational Studies ... experiment References references Bibliography Paul R. Rosenbaum 2002 . Observational Studies , 2nd ... DEFAULTSORT Observational Study Category Scientific method Category Statistical data types Category Design of experiments Category Observational study de Beobachtungsstudie es Estudio observacional ... more details
Unreferenced date January 2007 In marketing and the social sciences, observational research or field research is a social research technique that involves the direct observation of phenomena in their natural setting. This differentiates it from experimental techniques experimental research in which a quasi artificial environment is created to control for spurious factors, and where at least one of the variables is manipulated as part of the experiment. Observational techniques in context Compared with quantitative marketing research quantitative research and experimental techniques experimental research , observational research tends to be less reliability psychometric reliable but often more validity psychometric valid Citation needed date April 2007 . The main advantage of observational research is flexibility. The researchers can change their approach as needed. Also it measures behaviour directly, not reports of behaviour or intentions. The main disadvantage is it is limited to behavioural variables. It cannot be used to study cognitive or affective variables. Another disadvantage is that observational data is not usually generalizable. Three Approaches Generally, there are three types of observational research Covert observational research The researchers do not identify themselves. Either they mix in with the subjects undetected, or they observe from a distance. The advantages of this approach are 1 It is not necessary to get the subjects cooperation, and 2 The subjects behaviour will not be contaminated by the presence of the researcher. Some researchers have ethical misgivings with the deceit involved in this approach. Overt observational research The researchers identify themselves as researchers and explain the purpose of their observations. The problem with this approach is subjects may modify their behaviour when they know they are being watched. They portray ... used types of observational techniques are Personal observation observing product business ... more details
Other uses Social learning disambiguation Observational learning also known as vicarious learning , social learning , or modeling is a type of learning that occurs as a function of observing, retaining and replicating novel behavior executed by others. It is argued that reinforcement has the effect of influencing which responses one will partake in, more than it influences the actual acquisition of the new response. Although observational learning can take place at any stage in life, it is thought to be of greater importance during childhood , particularly as authority becomes important. The best role models are those a year or two older for observational learning. Because of this, social learning theory has influenced debates on the effect of television violence and parental role model s. Required conditions Unreferenced section date September 2007 Albert Bandura called the process of social learning modeling and gave four conditions required for a person to successfully model the behavior of someone else Attention to the model In order for the behavior to be learned, the observer must see the modeled behavior. Retention of details The observer must be able to recall the modeled behavior ... different from observational learning in that the latter leads to a change in behavior due to observing a model. Observational learning does not require that the behavior exhibited by the model is duplicated ... doll experiment is widely cited in psychology as a demonstration of observational learning and demonstrated ... their goals through violent acts. It is said that observational learning allows for learning without ... Machine learning Educational psychology Educational technology Emulation observational learning ... 13 816744 3, Paperback ISBN 0 13 816751 6 http www.thewolfwhisperer.com Wolf Whisperer Observational ... Busters Behavioral Therapists Observational K 9 Behavior, Learning by observing dog behavior and knowledge ... spackled imitation.pdf Full text Learning DEFAULTSORT Observational Learning Category Social ... more details
Observational comedy is a style of humor based on making remarks about commonplace aspects of everyday life . The humor, based on the premise of It s funny because it s true, ref http www.scientificamerican.com podcast episode.cfm?id its funny because its true 09 10 13 Scientific American It s Funny Because It s True, 13 Oct 2009 ref consists of observations made about sometimes very minor and superficial aspects of Western culture from airline peanuts to the Jared Fogle Jared Diet to the lines at Walgreens . Jokes may often begin with the phrase, Did you ever notice?... or What s the deal with...? , and may end with ... What s that about? . In the United States , the style was popularized by comedians such as Bill Cosby , George Carlin , Robert Klein , Richard Pryor , Jay Leno and David Letterman in the 1970s, continued by Bill Hicks , Larry David , Jerry Seinfeld , Ray Romano , and Mitch Hedberg in the 1990s. It is currently practiced by comedians such as Louis C.K. , Dave Chappelle , Dylan Moran , George Lopez , Russell Peters , Gabriel Iglesias , Rex Navarrete , Demetri Martin , Arj Barker , Patton Oswalt , Brian Regan , Chris Rock , Nick Swardson , Dane Cook , Daniel Tosh , Jim Gaffigan , Carlos Mencia , Craig Ferguson , Buddy Lewis comedian Buddy Lewis , Garrison Keillor , Greg Giraldo deceased , Lewis Black , Steve Byrne and Bill Maher . It is very popular in United Kingdom Britain , with comics such as Victoria Wood , Billy Connolly , Eddie Izzard , Jack Dee , Peter Kay , Jason Manford , Michael McIntyre , Lee Mack , Lee Evans comedian Lee Evans , Kevin Bridges and Russell Howard . It is also very popular in Australia , with comedians such as Carl Barron , Jimeoin , Dave Hughes and Adam Hills . In Canada , Rick Mercer and Russell Peters often present segments utilizing observational comedy. In Pakistan , Umer Sharif is known for observational comedy. In India , Raju ... dna h2g2 A930160 BBC H2G2 Article on Observational Comedy Acts Comedy footer Category Comedy ... more details
turned a telescope to the heavens and to record what he saw. Since that time, observational astronomy ... of observational astronomy is given by the region of the electromagnetic spectrum observed Optical .... Optical telescopes For much of the history of observational astronomy, almost all observation was performed ... telescope s. Astronomers have a number of observational tools that they can use to make measurements ... tools The key instrument of nearly all modern observational astronomy is the telescope ... popular Maksutov telescope . The photograph has served a critical role in observational astronomy for over ... determined based on the magnification of the instrument. A vital instrument of observational astronomy ... Observational science Related lists List of observatories List of radio telescopes Astronomy navbox DEFAULTSORT Observational Astronomy Category Observational astronomy Category Scientific observation ... more details
cosmology cTopic Experiments Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation , using instruments such as telescope s and cosmic ray detectors. Early observations The science of physical cosmology as it is practiced today had its subject material defined in the years following the Shapley Curtis debate when it was determined that the universe had a larger scale than the Milky Way galaxy . This was precipitated by observations that established the size of the universe size and the dynamics of the cosmos that could be explained by Einstein s General Theory of Relativity . In its infancy, cosmology was a speculative science based on a very limited number of observations and characterized by a dispute between steady state theorists and promoters of Big Bang cosmology. It was not until the 1990s and beyond that the astronomical observations would be able to eliminate competing theories and drive the science to the Golden Age of Cosmology which was heralded by David Schramm astrophysicist David Schramm at a United States ... stars, the observational limits imposed by the difficulty in measuring the minuscule parallaxes ... s Law and would serve as the observational foundation for the metric expansion of space expanding ... for their discovery. Modern observations Today, observational cosmology continues to test the predictions ..., the observational evidence for dark matter has heavily influenced theoretical modeling of structure ... supernova standard candle s, observational evidence for dark energy was obtained in the late 1990s ... through the WMAP experiment. Included here are the modern observational efforts that have directly ... generally take place from balloon or space based instruments. Current observational experiments ... background References references DEFAULTSORT Observational Cosmology Category Physical cosmology Category Observational astronomy es Cosmolog a observacional fr Cosmologie observationnelle pl Kosmologia ... more details
Error analysis Kinsley gaffe Politician inadvertently speaking the unspeakable truth Observational ...other uses The word error entails different meanings and usages relative to how it is conceptually applied. The concrete meaning of the Latin word error is wandering or straying . Unlike an illusion, an error ... else. Human behavior Image Napoleons retreat from moscow.jpg right thumbnail One error and its ... by Adolph Northen in the 19th century One reference differentiates between error and mistake as follows quote An error is a deviation from accuracy or correctness. A mistake is an error caused by a fault ... on my interpretation of what the signs meant, that would be an error. The first time it would be an error ... pas can be labels for certain instances of this kind of error. More serious departures from social norms ... forms should and should not be used. See also Error analysis . Image PrintingError.jpg thumb 400px ... that can culminate in stuttering. Medicine See medical error for a description of error in medicine ... in statistics error or residual is not a mistake but rather a difference between a computed, estimated, or measured value and the accepted true, specified, or theoretically correct value. See also Observationalerror . In science and engineering in general an error is defined as a difference between ... is the basis of operation for many types of Control system s, in which error is defined as the difference ... heating system the operation of the heating equipment is controlled by the difference the error ... s, machine s and system s and in such a way as to mitigate or preferably avoid the effects of error ... active. Other errors in engineered systems can arise due to human error , which includes cognitive bias . Human factors engineering is often applied to designs in an attempt to minimize this type of error by making systems more forgiving or error tolerant . In computational mechanics , when solving a system such as Ax b there is a distinction between the error &mdash the inaccuracy ... more details
of the observational method in applied soil mechanics, Geotechnique, 19, No. 1, pp. 171 187 ... of design for every foreseeable significant deviation of the observational findings from those predicted ... of actual conditions. Modification of design to meet actual conditions. The observational method is suitable ... blunder in applying the observational method is the failure to select in advance appropriate course .... 1999 . The Observational Method in ground engineering principles and applications. Report 185, CIRIA, London. Peck, R.B 1969 . Advantages and limitations of the observational method in applied soil mechanics ... more details
WORF.html Window Observational Research Facility WORF NASA ref Operations After transfer into the US ... Observations Capabilities of the Window Observational Research Facility on Board the International Space ... WORF.html article Window Observational Research Facility WORF External links http www.spaceandtech.com spacedata platforms iss worf sum.shtml ISS Window Observational Research Facility WORF Summary ... more details
can be enough for observational learning to occur work on pigeons ref Klein, E. D. & Zentall, T. R. 2003 ... , but copied in another study ref Hopper, L. M., S. P. Lambeth, et al. 2008 . Observational Learning ... Social learning and cumulative cultural evolution Observational learning Imitation Culture ..., evidence, and mechanisms . Animal Cognition, 9, 335 353. DEFAULTSORT Emulation Observational ... more details
Random errors are error s in measurement that lead to measurable values being inconsistent when repeated measures of a time invariant constant attribute or physical quantity quantity are taken. The word random indicates that they are inherently predictability unpredictable , and have null expected value , namely, they are scattered about the true value, and tend to have null arithmetic mean when a measurement is repeated several times with the same instrument. All measurements are prone to random error. Random error is caused by unpredictable fluctuations in the readings of a measurement apparatus, or in the experimenter s interpretation of the instrumental reading these fluctuations may be in part due to interference of the environment with the measurement process. The concept of random error is closely related to the concept of accuracy and precision precision . The higher the precision of a measurement instrument, the smaller the variability standard deviation of the fluctuations in its readings. Systematic versus random error Measurement errors can be split into two components random error and systematic error . ref name Taylor cite book title An Introduction to Error Analysis The Study of Uncertainties in Physical Measurements author John Robert Taylor url http books.google.com books?id giFQcZub80oC&pg PA94 page 94, 4.1 isbn 093570275X year 1999 publisher University Science Books ref Random error is always present in a measurement. It is caused by inherently unpredictable fluctuations in the readings of a measurement apparatus or in the experimenter s interpretation of the instrumental ... to the true value. If the cause of the systematic error can be identified, then it can usually ... is not accounted for. Incorrect zeroing of an instrument leading to a zero error is an example of systematic error in instrumentation. See also Errors and residuals in statistics Observationalerror References Reflist Category Measurement ca Error aleatori de Zufallsfehler es Error aleatorio id Galat ... more details
sample Errors and residuals in statistics Observationalerror References Refimprove date September ... are prone to systematic errors, often of several different types. Sources of systematic error may be imperfect calibration of measurement instruments zero error , changes in the surroundings environment ... can be either zero error or percentage error. For example, consider an experimenter taking a reading ... second on the clock then all of his results will be off by 1 second zero error . If the experimenter ... error in the calculated average of his results the final result will be slightly larger than ... error is an example of systematic error in instrumentation. Systematic errors may also be present .... For instance, the estimated oscillation frequency of a pendulum will be systematically in error if slight ... error equal to 2 of the actual temperature, and the actual temperature is 200 , 0 , or &minus 100 , the measured temperature will be 204 systematic error 4 , 0 null systematic error or &minus 102 systematic error &minus 2 , respectively. Thus, the temperature will be overestimated when it will be above ... to remove systematic error is through calibration of the measurement instrument. In a statistics statistical context, the term systematic error usually arises where the sizes and directions of possible ... quantity . If the zero reading is consistently above or below zero, a systematic error is present ... the mean. A systematic error is present if the stopwatch is checked against the speaking clock of the telephone ... to measure the wavelength of any other spectral line. Systematic versus random error Measurement errors can be divided into two components random error and systematic error. ref name Taylor cite book title An Introduction to Error Analysis The Study of Uncertainties in Physical Measurements author ... year 1999 publisher University Science Books ref Random error is always present in a measurement ... results for ostensibly the same repeated measurement. Systematic error cannot be discovered this way ... more details
Standard error can refer to Standard error statistics , the estimated standard deviation or error of a series of measurements Standard error stream , one of the standard streams in Unix like operating systems disambig pt erro padr o ... more details
Human Error may also refer to Human Error artist is a Polish electronic musician. Human Error album Human Error album , album by Unseen Terror Human Error Voyager episode Human Error Voyager episode , Star Trek Voyager episode Human Error House Human Error House episode , an episode of the series House M.D. Human Error, a 2008 single by New Zealand band The Datsuns Human Error, a song by aggrotech band Combichrist from album The Joy Of Gunz Human reliability Human error assessment and reduction technique , HEART a technique used in the field of human reliability disambig ... more details
wiktionary error An error is a mistake. Error may also refer to Error coin Error coram nobis , another type of writ to correct factual mistakes Error, a character from Zelda II The Adventure of Link Postage stamp error Appeal Writ of error , a writ historically issued for an appeal in common law cases Science Approximation error , error in scientific measurements Bias statistics Bias Error , in Computer Science, that part of the system state that is liable to lead to failure. Error message , a computer error message Errors and residuals in statistics Refractive error Standard error statistics Music Error band , an electro punk hardcore band from Los Angeles, California, US Errors band , a four piece post electro band from Glasgow, Scotland Sport Error baseball , a baseball concept See also Err disambiguation disambig ar ca Error cs Chyba de Error es Error fr Erreur gl Erro it Errore nl Error no Feil pl B d pt Erro desambigua o sl Napaka razlo itev fi Virhe sv Fel olika betydelser ... more details
There are many kinds of error in law. Reversible error can lead to a judgment being overturned on appeal. Harmless error is distinguished from plain error in that if error is preserved by the making of a timely objection law objection , the burden of proof is on the appellee to show that the error was harmless, but if error was not preserved, the burden of proof is on the appellant to show that the error was plain. ref cite web url http www.law.cornell.edu rules frcrmp Rule52.htm title Federal Rules of Criminal Procedure Rule 52 LII 2009 ed. publisher Law.cornell.edu date accessdate 2010 05 16 ref See also Standard of review References reflist Category Law Category Legal terms law stub ... more details
Multiple issues wikify December 2010 cleanup August 2008 The results of improper Administration business or execution of the research task are administrative errors . Such errors can be caused by carelessness, confusion, neglect, omission or some other blunder. ref William G. Zikmund 2003 , Business Research Methods, 7E. ISBN 0 03 035084 0. ref Four types of administrative error are Data Processing Error A category of administrative error that occurs because of incorrect data entry, incorrect computer programming or other error during data analysis. Sample Selection Error An administrative error caused by improper selection of a sample. Interviewer Error Admnistrative error caused by failure of an interviewer to record responses correctly. Interviewer Cheating The practice of filling in fake answers or falsifying questionnaires while working as an interviewer. Sources References reflist External links http www.zikmund.swcollege.com Business Research Methods DEFAULTSORT Administrative Error Category Office administration ... more details
In Programming language computer programming , error codes are enumerated messages that correspond to faults in a specific software application . They are typically used to identify faulty hardware , software , or incorrect user input in programming languages that lack exception handling , although they are sometimes also used in conjunction with exception handling. Error codes are not to be confused with return code s , although both are commonly used together in error handling. Some of the most severe error codes visible to users are the Stop error screen Blue Screen of Death codes provided by the Microsoft Windows Microsoft Windows operating systems . Error codes and exception handling Error codes are slowly disappearing from the programmer s environment as modern Object oriented programming object oriented programming languages replace them with Exception handling exceptions . Exceptions .... While it is considered poor practice in methodologies that use error codes and return codes to indicate failure, programmers often neglect to check return values for error conditions. That negligence can cause undesirable effects, as ignored error conditions often cause more severe problems later in the program. Exceptions are implemented in such a way as to separate the error handling code from the rest of the code. Separating the error handling code from the normal logic makes programs easier to write and understand, since one block of error handling code can service errors from any number of function calls. Exception handling also makes the code more readable than implementations with error ... for error conditions. See also Abort computing Aspect oriented programming Exit status Failure Static code analysis External links http www.barricane.com c error codes include errno Lists of Linux errno ... system error codes DEFAULTSORT Error Code Category Computer networking de Fehlercode es C digo de error ru sv Felkod ... more details
Abbe error , named after Ernst Abbe , also called sine error , describes the magnification of angular error over distance. For example, when one measures a point that is 1 meter away at 45 degrees, an angular error of 1 degree corresponds to a positional error of over 1.745 cm, equivalent to a distance measurement error of 1.745 . In machine design, some components are particularly sensitive to angular errors. For example, if the shaft of a lathe is angled slightly, the part will have errors in diameter far down the part. Abbe error can be detrimental to dead reckoning . Formula math epsilon h sin theta math External links http www.newport.com servicesupport Tutorials default.aspx?id 143 http www.aerotech.com products engref strait.html Category Error Category Trigonometry engineering stub it Errore di Abbe pl Postulat Abbego ... more details
Distinguish fatal system error In computing , a fatal error or fatal exception error is an error that causes a program to abort and may therefore return the user to the operating system . When this happens, data that the program was processing may be lost. A fatal error is usually distinguished from a fatal system error ref http www.webopedia.com TERM F fatal error.html ref ref http www.webopedia.com TERM S stop error.html ref colloquially referred to by the error message it produces as a Stop error screen blue screen of death . A fatal error occurs typically in any of the following cases An illegal instruction has been attempted Invalid data or Code computer programming code has been accessed An operation is not allowed in the current ring computer security ring or CPU modes CPU mode A program attempts to divide by zero . Only for integers with the IEEE floating point standard, this creates an infinity instead In some systems, such as Mac OS X and Microsoft Windows , a fatal error causes the operating system to create a data logging log entry or to save an image core dump of the process. References references External links http www.webopedia.com TERM F fatal exception error.html fatal exception error Webopedia http support.microsoft.com ?kbid 150314 What Are Fatal Exception Errors Microsoft Knowledge Base Screens of death operating system stub Category Computer errors ... more details
Error bars are used on graphs to indicate the Error Experimental science error , or uncertainty in a reported measurement. They give a general idea of how accurate a measurement is, or conversely, how far from the reported value the true error free value might be. Error bars often indicate one standard deviation of uncertainty, but may also indicate the Standard error statistics standard error . These quantities are not the same and so the measure selected should be stated explicitly in the graph or supporting text. Error bars can be used to visually compare two quantities, assuming various other conditions hold, to determine whether differences are statistically significant . They can also show how good a statistical fit the data has to a given function. Scientific papers in the experimental sciences are expected to include error bars on all graphs, though the practice differs somewhat between sciences, and each journal will have its own house style . See also Confidence interval Box plot External links http www.ncsu.edu labwrite res gt gt stat home.html Using Error Bars in your Graph North Carolina State University http www.graphpad.com faq viewfaq.cfm?faq 201 Is it better to plot graphs with SD or SEM error bars? Answer Neither Category Statistical terminology statistics stub de Fehlerbalken ko ... more details
mergefrom Numerical analysis Truncation and discretization error discuss Talk Numerical analysis Merging .22Errors.22 date March 2010 Unreferenced date December 2009 In numerical analysis , computational physics , and simulation , discretization error is error resulting from the fact that a function mathematics function of a continuum set theory continuous variable is represented in the computer by a finite number of evaluations, for example, on a lattice mathematics lattice dn . Discretization error can usually be reduced by using a more finely spaced lattice, with an increased Computational complexity theory computational cost . Related phenomena In signal processing , the analog of discretization is Sampling signal processing sampling , and results in no loss if the conditions of the sampling theorem are satisfied, otherwise the resulting error is called aliasing . Discretization error, which arises from finite resolution in the domain, should not be confused with quantization error , which is finite resolution in the range values , nor in round off error arising from floating point arithmetic. Discretization error would occur even if it were possible to represent the values exactly and use exact arithmetic it is the error from representing a function by its values at a discrete set of points, not an error in these values. Examples Discretization error is the principal source of error in methods of finite difference s and the pseudo spectral method of computational physics. When we define the derivative of math , f x math as math f x lim h rightarrow0 frac f x h f x h math or math f x approx frac f x h f x h math , where math , h math is a finitely small number, the difference between the first formula and this approximation is known as discretization error. See also Discretization Quantization error DEFAULTSORT Discretization Error Category Numerical analysis eo Diskretiga eraro ... more details
Unreferenced date December 2009 In statistics , the term error arises in two ways. Firstly, it arises in the context of decision making , where the probability of error may be considered as being the probability of making a wrong decision and which would have a different value for each type of error. Secondly, it arises in the context of statistical modelling for example regression where the model s predicted value may be in error regarding the observed outcome and where the term probability of error may refer to the probabilities of various amounts of error occurring. Hypothesis testing In hypothesis testing in statistics , two types of error are distinguished. Type I and type II errors Type I error s which consist of rejecting a null hypothesis that is true this amounts to a false positive result. Type I and type II errors Type II error s which consist of failing to reject a null hypothesis that is false this amounts to a false negative result. The probability of error is similarly distinguished. For a Type I error, it is shown as alpha and is known as the size of the test and is 1 minus the Specificity tests specificity of the test. It should also be noted that alpha is sometimes referred to as the confidence of the test, or the level of significance LOS of the test. For a Type II error, it is shown as beta and is 1 minus the Statistical power power or 1 minus the sensitivity tests sensitivity of the test. Statistical and econometric modelling The fitting of many statistical model models in statistics and econometrics usually seeks to minimise the difference between observed and predicted or theoretical values. This difference is known as an error , though when observed it would be better described as a Errors and residuals in statistics residual . The error is taken to be a random variable and as such has a probability distribution . Thus distribution can be used ... Of Error Category Error Category Statistical terminology statistics stub de Irrtumswahrscheinlichkeit ... more details
Encyclopedia
top
