In mathematics , computer science , telecommunication , information theory , and searching theory , errorcorrecting codes with feedback refers to errorcorrecting codes designed to work in the presence of feedback from the receiver to the sender. ref name standard See Harvnb Deppe 2007 and Harvnb Hill 1995 . ref Problem Alice the sender wishes to send a value x to Bob the receiver . The communication channel between Alice and Bob is imperfect, and can introduce errors. Solution An errorcorrectingcode is a way of coding theory encoding x as a message such that Bob will successfully understand the value x as intended by Alice, even if the message Alice sends and the message Bob receives differ. In an errorcorrectingcode with feedback, the channel is Two way communication two way Bob can send feedback to Alice about the message he received. Noisy feedback In an errorcorrectingcode without noisy feedback , the feedback received by the sender is always free of errors. In an errorcorrectingcode with noisy feedback , errors can occur in the feedback, as well as in the message. An errorcorrectingcode with noiseless feedback is equivalent to an Adaptive algorithm adaptive search strategy with errors. ref name standard History In 1956, Claude Shannon introduced the Discrete signal discrete memoryless channel with noiseless feedback. In 1961, Alfr d R nyi introduced the Bar Kochba game also known as Twenty questions , with a given percentage of wrong answers, and calculated the minimum number of randomly chosen questions to determine the answer. In his 1964 dissertation, Elwyn Berlekamp considered errorcorrecting codes with noiseless feedback. ref Harvnb Deppe 2007 . ref In Berlekamp s scenario, the receiver chose a subset of possible messages and asked the sender whether the given message was in this subset, a yes or no answer. Based on this answer, the receiver then chose ... location Cambridge . References reflist See also Noisy channel coding theorem Category Error detection ... more details
have the advantage of being handled with explicit blocks of code, separate from the rest of the code. 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 codes, since exception handling does not disrupt the flow of the code with frequent checks 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 ErrorCode Category Computer networking de Fehlercode es C digo de error ru sv Felkod ...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 ... more details
In coding theory , concatenated codes form a class of errorcorrectingcode s that are derived by combining an inner code and an outer code . They were conceived in 1966 by Dave Forney as a solution to the problem of finding a code that has both exponentially decreasing error probability with increasing ... an exponentially decreasing error probability with increasing length , and C sub out sub is a code with length N 2 sup nr sup that can be decoded in polynomial time of N , then the concatenated code ... symbols y nowiki nowiki sub i sub in error. Similarly, the inner code can reliably correct an input ... Jessie MacWilliams coauthors N.J.A. Sloane title The Theory of ErrorCorrecting Codes publisher ... channel. In fact, the probability of decoding error can be made to decrease exponentially as the block ... showed that concatenated codes could be used to achieve exponentially decreasing error probabilities ... with the code block length. Description File Concatenated codes diagram.png thumb upright 2 Schematic depiction of a concatenated code built upon an inner code and an outer code. Let C sub in sub be a n , k , d code, that is, a block code of length n , dimension vector space dimension k , minimum Hamming distance d , and code rate rate r n k , over an alphabet A math C in A k rightarrow A n math Let C sub out sub be a N , K , D code over an alphabet B with B A sup k sup symbols math C out B K rightarrow B N math The inner code C sub in sub takes one of A sup k sup B possible inputs, encodes into an n ... code with C sub in sub as inner code , denoted C sub out sub C sub in sub , is thus a code of length ... an exponentially decreasing error probability, even if C sub in sub has exponential decoding ... channel using the i th inner code. The Justesen code s are examples of generalized concatenated codes, where the outer code is a Reed Solomon code . Properties 1. The distance of the concatenated code C sub out sub C sub in sub is at least dD , that is, it is a nN , kK , D nowiki nowiki code ... more details
at Gare Montparnasse Montparnasse , France , 1895 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 or a mistake can sometimes be dispelled through knowledge ... moscow.jpg right thumbnail One error and its catastrophic results Napoleon s invasion of Russia Retreat ... 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 the fault being misjudgment, carelessness, or forgetfulness ... be an error. The first time it would be an error. The second time it would be a mistake since I should ... norms . See deviance . Gaffes and faux pas can be labels for certain instances of this kind of error ... class value judgments about what linguistic forms should and should not be used. See also Error analysis ... the gaffe in a developmental process that can culminate in stuttering. Medicine See medical error for a description of error in medicine. Science and engineering Image TrafficSignIsraelError.JPG .... In statistics , an errors and residuals in statistics error or residual is not a mistake but rather ... correct value. See also Observational error . In science and engineering in general an error is defined as a difference between the desired and actual performance or behavior of a system ... system s, in which error is defined as the difference between a set point and the process value. An example ... is controlled by the difference the error between the thermostat setting and the sensed air temperature ... avoid the effects of error, whether Hanlon s Razor unintentional or not . Such errors in a system ... 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 ... the error &mdash the inaccuracy in x &mdash and Residual numerical analysis residual the inaccuracy ... more details
Refimprove date December 2009 The error floor is a phenomenon encountered in modern iterated sparse graph code sparse graph based errorcorrecting codes like LDPC codes and turbo codes . When the bit error ratio BER curve is plotted for conventional codes like Reed Solomon codes under algebraic decoding or for convolutional codes under Viterbi decoder Viterbi decoding , the curve steadily decreases as the signal to noise ratio SNR condition becomes better. For LDPC codes and turbo codes there is a point after which the curve does not fall as quickly as before, in other words, there is a region in which performance flattens. This region is called the error floor region . The region just before the sudden drop in performance is called the waterfall region . ref Ryan, W. E. and Lin, S. Channel Codes Classical and Modern , Cambridge University Press ref Error floors are usually attributed to low weight codewords in the case of Turbo codes and trapping sets or near codewords in the case of LDPC codes . ref Thomas Richardson Error floors of LDPC codes . http ldpccodes.com papers ErrorFloors.pdf ref References Reflist DEFAULTSORT Error Floor Category Electronics terms Compsci stub ... more details
correctingcode needs only to cope with a single bit in error in each correction word in order ... cosmic ray s, especially with respect to Errorcorrectingcode schemes http www.edn.com article CA454636.html ... use forward error correction , incorporating redundant data into each word to create an errorcorrectingcode . Alternatively, roll back error correction can be used, detecting the soft error with an Error detection and correction error detecting code such as Error detection and correction Parity ...Refimprove date November 2011 distinguish software error In electronics and computing , a soft error is an error in a signal or datum which is wrong. Errors may be caused by a wikt defect defect , usually understood either to be a mistake in design or construction, or a broken component. A soft error ... observing a soft error, there is no implication that the system is any less reliable than before. In the spacecraft industry this kind of error is called a single event upset . An error occurence ... typically can be remedied by cold booting the computer. A soft error will not damage a system s hardware ... level soft error These errors occur when the radioactive atoms in the chip s material decay and release ... to decay. system level soft error These errors occur when the data being processed is hit with a noise ... bit, which can cause errors in addressing or processing program code. The bad data bit can even be saved in memory and cause problems at a later time. If detected, a soft error may be corrected by rewriting correct data in place of erroneous data. Highly reliable systems use error correction ... data, or even to discover that an error is present at all. In addition, before the correction ... in semiconductor storage. Critical charge Whether a circuit experiences a soft error depends on the energy ... likely to suffer an error. This combination of capacitance and voltage is described by the critical ... error by alpha particle emission. The positively charged alpha particle travels through the semiconductor ... more details
For 2003 film Syntax Error film Unreferenced date December 2009 In computer science , a syntax error refers to an error in the Syntax programming languages syntax of a sequence of characters or Token parser tokens that is intended to be written in a particular programming language . For compiled language s syntax errors occur strictly at compiler compile time . A program will not compile until all syntax errors are corrected. For interpreted language s, however, not all syntax errors can be reliably detected until Run time program lifecycle phase run time , and it is not necessarily simple to differentiate a syntax error from a Logic error semantic error many don t try at all. A syntax error may also occur when an invalid equation is entered into a calculator . This can be caused, for instance, by opening brackets without closing them, or less commonly, entering several decimal point s in one number. In Java the following is a syntactically correct statement system.out.println Hello World while the following is not system.out. println Hello World A compiler will flag a syntax error when given source code that does not meet the requirements of the language grammar. Category Computer errors compu prog stub de Syntaxfehler ko is M lfr ivilla kk ms Ralat sintaks pl B d sk adniowy sv Syntax error ... more details
for logical error in argument Fallacy unreferenced date November 2007 Portal Software Testing In computer programming , a logic error is a Software bug bug in a program that causes it to operate incorrectly, but not to terminate abnormally or crash computing crash . A logic error produces unintended or undesired output or other behavior, although it may not immediately be recognized as such. Logic errors occur in both Compiler compiled and Interpreter computing interpreted languages. Unlike a program with a syntax error , a program with a logic error is a valid program in the language, though it does not behave as intended.The only clue to the existence of logic errors is the production of wrong solutions. Common causes The mistake could be the logical error in a Statement programming statement for example, a wrong or incorrect formula , an error in an algorithm , or even the wrong algorithm selected. Debugging logic errors One of the ways to find these type of errors is to output the program s Variable programming variables to a file or on the screen in order to define the error s location in code. Although this will not work in all cases, for example when calling the wrong subroutine , it is the easiest way to find the problem if the program uses the incorrect results of a bad Algorithm mathematical calculation . Examples This example in C programming language C contains a logic error. After code scanf code , code money in store code is checked instead of code money code . source lang c include stdio.h int money, money in store int main do printf Enter amount of money to give to store 0 to exit scanf d , &money if money in store 0 Should be if money 0 printf d money on exit n , money in store exit 0 money in store money while 1 return 0 source See also Syntax error Category Computer errors compu prog stub bg de Logischer Fehler fa it Errore di semantica ... more details
Compilation error refers to a state when a compiler fails to compile a piece of computer program source code , either due to errors from the compiler itself, or syntax errors in the code. A compilation error message often helps computer programmer programmers debugging the source code for possible syntax error s. Examples Common C compilation errors Undeclared identifier, e.g. code doy.cpp In function int main doy.cpp 25 DayOfYear undeclared first use this function code ref name common c compiler and linker errors cite web title Common C Compiler and Linker Errors url http www.csee.umbc.edu courses undergraduate 341 misc CommonErrors.shtml ref This means that the variable DayOfYear is trying to be used before being declared. Common function undeclared, e.g. code xyz.cpp In function int main xyz.cpp 6 cout undeclared first use this function code ref name common c compiler and linker errors This means that the programmer most likely forgot to include iostream . Parse error, e.g. code somefile.cpp 24 parse error before something code ref name compiler linker and run time errors cite web title Compiler, Linker and Run Time Errors url http www.cs.bu.edu teaching cpp debugging errors ref This could mean that a semi colon is missing at the end of the previous statement. Internal Compiler Errors These errors are not the same as normal compiler errors they re caused by compiler itself and not the source code you re trying to compile. Which means, it s a bug in the compiler itself instead of the source code. internal compiler error pre somefile.c 1001 internal compiler error Segmentation fault Please submit a full bug report, with preprocessed source if appropriate. See http bugs.gentoo.org for instructions. pre References reflist Category Debugging Category Computer errors compu prog stub ... 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 webopedia.com ref ref http www.webopedia.com TERM S stop error.html webopedia.com 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 zh ... more details
either with a try catch with an empty catch clause, or by executing code depending on the returning error status Example of try catch error hiding C code source lang cpp include iostream ... of nested empty try catch Error Hiding code , and any anomaly is extremely difficult to trace ... returning error hiding VBScript code source lang vb If doSomething Then If doSomethingElse Then If anotherDoSomething ... some error happens, it is hidden by the code because it s error prone or simply verbose to add ...Unreferenced date March 2009 Image Iceweasel error hiding.png thumb Firefox Iceweasel hiding a system error message TCP IP error errno.h ECONNREFUSED behind a vague description. Error hiding is an anti pattern in computer programming . The programmer hides error messages by overriding them with exception handling . As a result of this the root error message is hidden from the user hence error hiding and so they will not be told what the actual error is. Error hiding is a bane of support engineers ... is going wrong. A common argument for error hiding is the desire to hide complexity from the user. Frequently best practice is to raise an exception to the user to hide a complex error message but to save the full error message to an error log which a support engineer can access to resolve the problem ... import failed end This code fragment attempts to open a file and read it into memory. If it fails ... files containing detailed records of the state of the application when the error occurred. Sometimes error hiding is a valid activity, for example accessing the contents of a file that does not exist in Java programming language Java version 1.3 or older would result in an code IOException code message without any reference to the missing file. In this case is would be sensible to hide the error and raise ... information can be obtained. Another justification for Error Hiding is to avoid component crashing in case of failure. Despite the error, the component continues its job. The user and the testers never ... more details
error messages Abort, Retry, Fail? Bad command or file name PC LOAD LETTER Lp0 on fire Not a typewriter Blue Screen of Death HTTP 404 Message format The form that error messages take varies between operating systems and programs. Error messages on hardware devices, like computer peripherals, may take the form of dedicated lights indicating an error condition, a brief code that needs to be interpreted ...Refimprove date September 2008 An error message is information displayed when an unexpected condition ... , error messages are often displayed using dialog box es. Error messages are used when user intervention ... such as warning a computer user that they are almost out of hard disk drive hard disk space . Error ... computer hardware computer hardware device. Proper design of error messages is an important topic in usability and other fields of human computer interaction . Common error messages The following error messages are commonly seen by modern computer users Access denied This error occurs if the user ... can no longer run because of a severe error. It is roughly analogous to a kernel panic on Linux , Unix or Mac OS X . The device is not ready This error most often occurs when there is no floppy disk ... the error. Alternatively, the file simply might not exist, or the user has mistyped its name. Low Disk Space This error occurs when the hard drive is nearly full. To fix this, the user should close ..., or other files after they have been backed up , or get a bigger hard drive. Out of memory This error ..., error messages may take the form of text printed to a console, or they may be presented as part of a graphical user interface . Error messages are often presented as a dialog box , which makes them to cause a following mode error in the user interaction. In many cases the original error can be avoided by error prevention techniques. Instead of raising an error message the system design should have avoided the conditions that caused the error. ref Raskin, Jef 2000. The Humane Interface , Addison ... 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 legal burden of proof 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
the use of this errorcode in its newer cameras. In its place it has adopted the more common term lens error that other manufacturers use. As such, its newer cameras report this term when the problem ...Image Canon Ixus II with E18 error.jpg thumb right The E18 error as it appears on a camera s LCD display an Canon Digital IXUS Ixus II in this example . The E18 error is an error message on Canon Inc. Canon digital camera s. The E18 error occurs when anything prevents the zoom lens from properly extending or retracting. ref definition The error has become notorious in the Canon user community as it can completely disable the camera, requiring expensive repairs. ConsumerAffairs.com reports that the lens has a feature called bellows claw, which is a gear that physically extends and retracts the lens. A piece that holds the lens, the barrier plate, is not large enough and can sometimes cause the bellows ... is a black screen that only contains the error message, E18. Another problem mentioned on the site .... The buildup freezes up the ability of the lens to open. Although the use of the E18 error ... the lens to extend with the lens restricted in its movement, causing the error. Another cause is that sand .... The lens error will occur once these materials work their way into the lens mechanism. Another major ... that no sand particles are clinging to it a single grain can jam the camera . Repairing the E18 error ... that connecting the camera to the TV completely resolved the E18 error. 2 A camera lens is out ... Links , and may also be found on search engines when the more common term lens error is utilized for the search ... error and may file a class action lawsuit against Canon. ref classaction2 Dead link date November ... e18.bitnet.cx comments.php E18 error experiences log list of cameras affected by this error along ... http camerarepair.blogspot.com 2007 12 fixing lens error on digital camera.html E18 lens error ... Use dmy dates date November 2010 DEFAULTSORT E18 Error Category Canon PowerShot cameras Category ... more details
of the error of the channel code can made to go to zero as the block length goes to infinity. In practical ...Unreferenced date February 2008 In information theory , the error exponent of a channel capacity channel code or data compression source code over the block length of the code is the logarithm of the error probability. For example, if the probability of error of a decoder drops as e sup n sup , where n is the block length, the error exponent is . Many of the information theory information theoretic ... of the code cannot be taken to go to infinity. Therefore it is important to study how the probability of error drops as the block length go to infinity. Error exponent in channel coding For time invariant ... scheme that can be used to ensure that the probability of block error is less than 0 for sufficiently ... capacity, the probability of block error at the receiver goes to one as the block length goes to infinity ... is transmitted, the probability that X 1 is incorrectly detected as X 2 is math P mathrm error 1 ... for math s 0 math Thus, math P mathrm error 1 to 2 le sum x 1 n 2 Q x 1 n 2 left frac p y 1 n x 2 n ... of confusing X 1 with any message is bounded by math P mathrm error 1 to mathrm any le M rho sum ... of math X 1 n 1 , y 1 n math math P mathrm error 1 to mathrm any le M rho sum y 1 n left sum x ... math P mathrm error 1 to mathrm any le M rho sum y 1 n left sum x 1 n Q x 1 n p y 1 n x 1 n frac 1 1 ... memoryless nature of the channel math P mathrm error 1 to mathrm any le M rho prod i 1 n sum y i ... is identically distributed and thus stationary math P mathrm error 1 to mathrm any le M rho ... probability of error becomes math P mathrm error le exp n E o rho,Q rho R . math Q and math rho math should be chosen so that the bound is tighest. Thus, the error exponent can be defined as math E r ... June 2008 Error exponent in source coding For time invariant discrete memoryless sources The source ... to minimize the probability of error the decoder will decode to the source sequence math X 1 ... more details
Image Error Function.svg thumb right 400px Plot of the error function In mathematics , the error function also called the Gauss error function is a special function non Elementary function elementary of Sigmoid ... error function , denoted erfc , is defined as math begin align operatorname erfc x & 1 operatorname erf x & frac 2 sqrt pi int x infty e t 2 ,dt. end align math The imaginary error function , denoted erfi , is defined as math operatorname erfi z i , , operatorname erf i ,z math The complex error ... erfc ix e x 2 1 i , , operatorname erfi x math The name error function The error function ... stuck. The error function is the integral of the Gaussian function curve the bell curve or normal distribution . As a result, the error function gives the probability that a measurement, under the influence .... This usage is similar to the Q function , which in fact can be written in terms of the error function ... ComplexEx2.jpg caption1 Integrand exp &minus z sup 2 sup image2 ComplexErf.jpg caption2 erf z The error ... The error function is an entire function it has no singularities except that at infinity and its ..., one obtains the error function s Taylor series as math operatorname erf z frac 2 sqrt pi sum n ... 1 sup th sup term considering z as the first term . The error function at is exactly 1 see Gaussian integral . The derivative of the error function follows immediately from its definition math frac rm d rm d z , mathrm erf z frac 2 sqrt pi ,e z 2 . math An antiderivative of the error function is math z , operatorname erf z frac e z 2 sqrt pi . math Inverse functions The inverse error ... terms are given in entry A002067. Note that the error function s value at is equal to 1. The inverse complementary error function is defined as math operatorname erfc 1 1 z operatorname erf 1 z . math Asymptotic expansion A useful asymptotic expansion of the complementary error function and therefore also of the error function for large x is math mathrm erfc x frac e x 2 x sqrt pi ... more details
Unreferenced date March 2011 Notability date March 2011 Infobox Book name Night Of Error title orig translator image image Night Of Error.JPG 200px Ideally 1st edition cover image caption 2000 paperback edition author Desmond Bagley illustrator cover artist country United Kingdom language English language English series genre Thriller genre Thriller Novel publisher House of Stratus release date 1984 media type Print Hardcover & Paperback pages 302 pgs isbn 1 842 32015 7 oclc 43971653 preceded by Windfall novel Windfall followed by Juggernaut novel Juggernaut Night Of Error is a novel written by English people English author Desmond Bagley , and was first published in 1984 in literature 1984 . Plot introduction After receiving news that his brother Mark has died in suspicious circumstances in the Pacific , marine biologist Mike Trevelyan discovers that Mark s latest research may have discovered a lucrative source of manganese beneath the sea. With only two clues a notebook in code and a lump of deep sea rock Mike s investigations trigger the start of a hazardous marine expedition and a violent confrontation far from civilisation. Desmond Bagley Category 1984 novels Category Novels by Desmond Bagley thriller novel stub ... more details
Error bars are a graphical representation of the variability of data and 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 compare visually two quantities if various other conditions hold. This can determine whether differences are statistically significant . Error bars 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
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
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
Unreferenced date December 2009 In statistics , a forecast error is the difference between the actual or real and the predicted or forecasting forecast value of a time series or any other phenomenon of interest. In simple cases, a forecast is compared with an outcome at a single time point and a summary of forecast errors is constructed over a collection of such time points. Here the forecast may be assessed using the difference or using a proportional error. By convention, the error is defined using the value of the outcome minus the value of the forecast. In other cases, a forecast may consist of predicted values over a number of lead times in this case an assessment of forecast error may need to consider more general ways of assessing the match between the time profiles of the forecast and the outcome. If a main application of the forecast is to predict when certain thresholds will be crossed, one possible way of assessing the forecast is to use the timing error&mdash the difference in time between when the outcome crosses the threshold and when the forecast does so. When there is interest ... between the peak value of the outcome and the value forecast for that time point. Forecast error can be a calendar forecast error or a cross sectional forecast error, when we want to summarize the forecast error over a group of units. If we observe the average forecast error for a time series of forecasts for the same product or phenomenon, then we call this a calendar forecast error or time series forecast error. If we observe this for multiple products for the same period, then this is a cross sectional performance error. Reference class forecasting has been developed to reduce forecast error. See also Forecasting Calculating Demand Forecast Accuracy Mean squared prediction error Errors and residuals in statistics Optimism bias Reference class forecasting DEFAULTSORT Forecast Error Category Error Category Estimation theory pl B dy prognozy ex post ... more details
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