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 model physics lattice . Discretization error can usually be reduced by using a more finely spaced lattice, with an increased Computational complexity theory computational cost . 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. 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. See also Discretization Linear multistep method Quantization error DEFAULTSORT Discretization Error Category Numerical analysis eo Diskretiga eraro ... 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 ... zeroing of an instrument leading to a zero error is an example of systematic error in instrumentation. See also Errors and residuals in statistics Observational error References Reflist 1 Category Measurement ca Error aleatori de Zuf llige Abweichung es Error aleatorio lt Atsitiktin paklaida pl B d ... more details
Multiple issues howto September 2009 orphan September 2008 notability October 2008 In photography , a focus error is an aberration of the autofocus thus, the camera focuses a subject but the lens is not aligned correctly, causing a blurry image . In digital photography , the focus error is especially an error message on Fujifilm FinePix digital camera s, usually caused by dirt in the lens mechanism. To avoid any further damage, the camera electronics totally disables the autofocus system and refuses to take any still image. If out of warranty, the repair costs can easily exceed US 100. However, other brands suffer from similar faults, like the Canon E18 error or the Nikon Coolpix SYSTEM ERROR , and some users manage to bring their devices back to life by disassembling and cleaning the lens. External links http www.mathematik.uni marburg.de haim focuserr.htm Fujifilm FinePix A303 Focus Error Repair Guide DEFAULTSORT Focus Error Category Digital cameras Category Fujifilm cameras ... 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 Category Parsing Category Programming language theory compu prog stub de Syntaxfehler ko is M lfr ivilla kk ms Ralat sintaks pl B d sk adniowy sv Syntax error ... more details
unreferenced date October 2011 Image Exponential.png thumb 300px right The graph illustrates how an exponential growth surpasses both linear and cubic growths. Notice how quickly and substantially an error can be compounded over time. Exponential error is an idea expressing how a very small error can compound itself over time. It can be characterized as the exponential growth of an error or the application of exponential growth in terms of an error. See also Exponential growth Computational complexity theory Scalability of algorithms Theory of computation Computer science Analysis of algorithms Math stub Category Exponentials ar ... more details
In finance , tracking error is a measure of how closely a portfolio follows the index to which it is benchmarked. The best measure is the root mean square of the difference between the portfolio and index returns. Many portfolios are managed to a benchmark, typically an index. Some portfolios are expected to replicate, before trading and other costs, the returns of an index exactly e.g., an index fund , while others are expected to actively manage the portfolio by deviating slightly from the index in order to generate active returns. Tracking error also called active risk is a measure of the deviation from the benchmark the aforementioned index fund would have a tracking error close to zero, while an actively managed portfolio would normally have a higher tracking error. Dividing portfolio active return by portfolio tracking error gives the information ratio , which is a risk adjusted performance measure. Definition If tracking error is measured historically, it is called realized or ex post tracking error. If a model is used to predict tracking error, it is called ex ante tracking error. Ex post tracking error is more useful for reporting performance, whereas ex ante tracking error is generally used by portfolio managers to control risk. Various types of ex ante tracking error models ... factor fixed income models. Formulas The ex post tracking error formula is the root mean square ... in terms of volatility of active returns makes sense, however, if the tracking error is to be used in an information ratio . Early papers ref e.g., Richard Roll, A Mean Variance Analysis of Tracking Error ... error volatility and are a possible source for the second conception of tracking error the volatility ... Error YouTube http monevator.com 2011 01 18 tracking error E2 80 93 a hidden cost Tracking error A hidden cost of passive investing http moneyterms.co.uk tracking error Tracking error Category Financial risk de Tracking Error fr Tracking error it Tracking error nl Tracking error sv Aktiv risk ... more details
The approximation error in some data is the discrepancy between an exact value and some approximation to it. An approximation error can occur because the measurement of the data is not precise due to the instruments. e.g., the accurate reading of a piece of paper is 4.5cm but since the ruler does not use decimals, you round it to 5cm. or approximations are used instead of the real data e.g., 3.14 instead ... of an algorithm in numerical analysis indicates how the error is propagated by the algorithm. Overview One commonly distinguishes between the relative error and the absolute error . The absolute error .... The relative error is the absolute error divided by the magnitude of the exact value. The percent error is the relative error expressed in terms of per 100. As an example, if the exact value is 50 and the approximation is 49.9, then the absolute error is 0.1 and the relative error is 0.1 50 0.002. The relative error is often used to compare approximations of numbers of widely differing size for example, approximating the number 1,000 with an absolute error of 3 is, in most applications, much worse than approximating the number 1,000,000 with an absolute error of 3 in the first case the relative error is 0.003 and in the second it is only 0.000003. Another example would be if you measured a beaker and read, 5mL. The correct reading would have been 6mL. This means that your error Approximate error would be 16.66666.. error. Definitions Given some value v and its approximation v sub approx sub , the absolute error is math epsilon v v text approx , math where the vertical bars denote the absolute value . If math v ne 0. math the relative error is math eta frac v v text approx v left frac v v text approx v right left 1 frac v text approx v right , math and the percent error is math ... Percentage error Mathapplied stub algebra stub Category Numerical analysis ar bg ca Error d aproximaci de Fehlerschranke es Error de aproximaci n eo Ekarto fr ... more details
In statistics , sampling error or estimation error is the amount of inaccuracy in estimating some value ... of inaccuracy is commonly referred to as an Errors and residuals in statistics error . ref ..., ISBN 0 387 40620 4 ref Sampling error can be measured and quoted in many different ways, but in practice the reported error itself is almost always an estimate of the real error rather than an absolute measure of the error which would usually require analyzing the entire population . Description Random sampling In statistics , sampling error is the Errors and residuals in statistics error caused by observing a sample instead of the whole population. ref name Sarndal The sampling error can be found ... 2010 In nursing research, a sampling error is the difference between a sample statistic used to estimate ... error is typically unknown. Sampling error also refers more broadly to this phenomenon of random sampling variation. An example of a sampling error in evolution is genetic drift a change is a population ... represent the original population. What makes the bottleneck effect a sampling error is that certain ... it a sampling error. Another example of genetic drift that is a sampling error is the founder effect ... error. ref Citation last1 Campbell first1 Neil A. last2 Reece first2 Jane B. title Biology publisher Benjamin Cummings pages 450 451 date year 2002 isbn ref The likely size of the sampling error can generally ... Fritz Scheuren 2005 . What is a Margin of Error? , Chapter 10, in http www.amstat.org sections srms ... probability probabilistic estimates of the likely size of the sampling error for a particular statistic or estimator . These are often expressed in terms of its standard error statistics standard error ... errors . Non sampling error Sampling error can be contrasted with non sampling error . Non sampling error is a catch all term for the deviations from the true value that are not a function of the sample chosen, including various systematic error s and any random errors that are not due to sampling ... more details
of safety tolerance in engineering Tolerance engineering distinguish Margin for Error File Marginoferror95.PNG ... line segment s , the corresponding margins of error on the left , and sample sizes on the right ... indicated by the corresponding segment. The larger the sample is, the smaller the margin of error is. The margin of error is a statistic expressing the amount of random sampling error in a statistical survey survey s results. The larger the margin of error, the less faith one should have that the poll ... population population . Margin of error occurs whenever a population is incompletely sampled. Explanation The margin of error is usually defined as the radius or half the width of a confidence interval ... A versus product B. When a single, global margin of error is reported for a survey, it refers to the maximum margin of error for all reported percentage s using the full sample from the survey. If the statistic is a percentage, this maximum margin of error can be calculated as the radius of the confidence interval for a reported percentage of 50 . The margin of error has been described as an absolute ..., then we say the margin of error is 5 percentage points. As another example, if the true value is 50 ... of error is 5 people. In some cases, the margin of error is not expressed as an absolute quantity ... of error would be 5 people. If we use the relative definition, then we express this absolute margin of error as a percent of the true value. So in this case, the absolute margin of error is 5 people, but the percent relative margin of error is 10 because 5 people are ten percent of 50 people ... confidence intervals, the margin of error can be defined for any desired confidence level, but usually ... of error around the reported percentage would include the true percentage. Along with the confidence ... the magnitude of the margin of error. A larger sample size produces a smaller margin of error, all else remaining equal. If the exact confidence intervals are used, then the margin of error takes ... more details
In numerical analysis and scientific computing , truncation error is the error made by truncating an infinite sum and approximating it by a finite sum. For instance, if we approximate the sine function by the first two non zero term of its Taylor series, as in math sin x approx x tfrac16 x 3 math for small math x math , the resulting error is a truncation error. It is present even with infinite precision arithmetic, because it is caused by truncation of the infinite Taylor series to form the algorithm. Often, truncation error also includes discretization error , which is the error that arises from taking a finite number of steps in a computation to approximate an infinite process. For example, in numerical methods for ordinary differential equations , the continuously varying function that is the solution of the differential equation is approximated by a process that progresses step by step, and the error that this entails is a discretization or truncation error. See Truncation error numerical integration for more on this. Occasionally, round off error the consequence of using finite precision Floating point floating point numbers on computers is also called truncation error, especially if the number is rounded by truncation . References Citation last1 Atkinson first1 Kendall A. title An Introduction to Numerical Analysis publisher John Wiley & Sons location New York edition 2nd isbn 978 0 471 50023 0 year 1989 page 20 Citation last1 Stoer first1 Josef last2 Bulirsch first2 Roland title Introduction to Numerical Analysis publisher Springer Verlag location Berlin, New York edition 3rd isbn 978 0 387 95452 3 year 2002 page 1 . Category Numerical analysis pl B d metody pt Erro de truncamento ... more details
A description error is an error that occurs when a person performs an action on an object that is not the intended object. This error can be very disorienting and usually causes a brief loss of situation awareness or automation surprise if noticed right away. But much worse, if it goes unnoticed, it could cause more serious problems. So allowances such as clearly highlighting a selected item should be made in interaction design . External links http www.usabilityfirst.com glossary term 1200.txl Definition at Usabilityfirst.com Category Human behavior design stub pt Erro de descri o ... more details
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 ... 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 ... 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 ... on the returning error status Example of try catch error hiding C code source lang cpp include iostream ... strerror errno input file result cout result catch ... Error messages are for wussies cout Result is result ... of nested empty try catch Error Hiding code , and any anomaly is extremely difficult to trace to its origin, increasing maintenance costs, only to keep up an appearance of robustness. Example of error 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 ..., never discovered . Manifestations in languages that support checked exceptions Error hiding is one ... more details
A C2 error is a read error of a compact disc . C2 errors can be to a degree recovered by the hardware error detection and correction scheme. A CD drive can have extraction errors when the data on the disc is not readable due to scratches or smudges. The drive can compensate by supplying a best guess of what the missing data was, then supplying the missing data. C2 error correction is an analysis over many interleaved Compact disc Frame frames , an improvement over C1 error C1 error correction , which analyzed just one frame, resulting in more accurate data correction. ref Decker, Logan Winter 2002 . How To... Make MP3s . Maximum PC . ref C2 error correction codes are also used by the Digital Audio Tape DAT format. Some copy protection schemes add false C2 errors to discs to discourage copying. References reflist External links http www.feurio.com English faq faq vocable c2error.shtml Feurio FAQ C2 errors http www.cdmasteringservices.com digitalerrors.htm Explaining Common CD Errors Category Compact Disc Category DVD compu hardware stub ... more details
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 Abort, Retry, Fail? Bad command or file name PC LOAD LETTER Lp0 on fire Not a typewriter ... error message . With the rise of Web 2.0 services such as Twitter , end user facing error messages ... or Error Mascots. ref cite web last Rintel first Sean title The Evolution of Fail Pets Strategic Whimsy and Brand Awareness in Error Messages url http uxmag.com articles the evolution of fail pets publisher ... System 7 emoticon style face Twitter Fail Whale 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 ..., 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 ... more details
Infobox Album See Wikipedia WikiProject Albums Name Error Type EP Artist Error band Error Cover Error Error.jpg Released February 24, 2004 Recorded Genre Industrial music Industrial , hardcore punk , digital hardcore Length 17 12 Label Epitaph Records Producer Error band Error Reviews Allmusic Rating 4 5 Allmusic class album id r676556 pure url yes link Rolling Stone Rating 2 5 http www.rollingstone.com artists error albums album 123640 review 5942814 error link Last album This album Error br 2004 Next album ... Error is the self titled debut extended play EP by Error band Error , released by Epitaph Records in 2004. Although not an official member, Greg Puciato of the Dillinger Escape Plan was asked to record vocals for the EP, as the band was without a vocalist at the time. Track listing tracklist writing credits yes title1 Nothing s Working note1 writer1 Atticus Ross , Leopold Ross , Brett Gurewitz length1 2 38 title2 Homicide note2 writer2 999 band Guy Martin Days, Keith Roger Lucas length2 3 46 title3 Burn in Hell note3 writer3 Ross, Ross, Gurewitz length3 3 10 title4 Jack the Ripper note4 writer4 Ross, Ross, Gurewitz length4 3 34 title5 Brains Out note5 writer5 Ross, Ross, Gurewitz length5 4 02 Personnel Greg Puciato lead vocals Atticus Ross programming Brett Gurewitz guitar, bass Leopold Ross drums, percussion Joey Karam Moog synthesizer on Jack the Ripper Published by Sick Muse Songs Administered by EMI EMI Music Publishing Design by Nick Pritchard Category 2004 EPs Category Epitaph Records EPs 2000s punk album stub ... more details
An error account is a type of account used for storing compensation for errors in trading, a transaction that is not posted in a timely manner because of inconsistencies, such as an incorrect account or routing numbers to the wrong name on the account, producing a claim that needs to be resolved as soon as possible so payments can be made. Transaction processing When many hundreds or thousands of transactions are being done each day, and whenever there is human input involved, error accounts are necessary to keep the audit trail intact. Error accounts also play a role in improving customer service . GAAP recommends daily or weekly monitoring of error accounts depending on volume and transaction size. It is typically up to the company or applicable government department s accounting department to monitor the error accounts that it has in place. Error accounts, if not monitored correctly, can lead to disaster as in Nick Leeson s use of an error account at Barings Bank . ref cite news url http news.bbc.co.uk 2 hi business 375259.stm work BBC News title How Leeson broke the bank date 1999 06 22 accessdate 2010 05 02 ref Error accounts can be implemented in manual accounting as well, but this is much less common in the developed world since personal computers became pervasive. See also Generally Accepted Accounting Principles International Financial Reporting Standards International Accounting Standards Board Center for Audit Quality Transaction processing References nofootnotes date March 2009 references http dictionary.bnet.com definition error account.html cite web title error account definition Dictionary MSN Encarta BOT GENERATED TITLE url http encarta.msn.com dictionary 561538588 error account.html work archiveurl http www.webcitation.org 5kwbute2u archivedate 2009 10 31 deadurl yes http jobfunctions.bnet.com abstract.aspx?docid 147896 http www.acpsec.org en secretariat Dr Kathie Cooper.ppt Forensic Accounting use of Error Accounts http www.sciencedirect.com science ... more details
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. Combining forecasts has also been shown to reduce forecast error. ref cite web url http marketing.wharton.upenn.edu ideas pdf Armstrong ... Forecast Accuracy Mean squared prediction error Errors and residuals in statistics Optimism bias Reference class forecasting References reflist DEFAULTSORT Forecast Error Category Error Category ... more details
Error analysis is the study of kind and quantity of error that occurs, particularly in the fields of applied mathematics particularly numerical analysis , applied linguistics and statistics . Error analysis in numerical modeling In numerical simulation or modeling of real systems, error analysis is concerned ... x,y math . Error analysis deals with the propagation of the numerical error s in math scriptstyle ... bar y math to error in math scriptstyle z math around a mean math scriptstyle bar z math . ref cite ... 186&ndash 189 date 1996 publisher Springer id ISBN 0412042010 ref In numerical analysis, error analysis comprises both forward error analysis and backward error analysis . Forward error analysis involves ... the bounds on the error in the approximation i.e., to find math scriptstyle epsilon math such that math scriptstyle 0 , le , z z , le , epsilon math . Backward error analysis involves the analysis ... id ISBN 0070552215 ref anchor Error analysis in language teaching Error analysis in second language acquisition Main Error analysis linguistics In second language acquisition , error analysis studies the types and causes of speech error language errors . Errors are classified ref Cf. Bussmann, Hadumod 1996 , Routledge Dictionary of Language and Linguistics , London Routledge, s.v. error analysis. A comprehensive bibliography was published by Bernd Spillner 1991 , Error Analysis , Amsterdam ... norm vs. system Error analysis in SLA was established in the 1960s by Stephen Pit Corder ... Error analysis was an alternative to contrastive analysis , an approach influenced by behaviorism through ... languages to predict errors. Error analysis showed that contrastive analysis was unable to predict ... of Language transfer language transfer . A key finding of error analysis has been that many learner ... language. Error analysis in molecular dynamics simulation In molecular dynamics MD simulations ... to the statistical error due to random fluctuation in the measurements. For a series of M ... more details
Observational error 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 observational error 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
Unreferenced date December 2009 Orphan date December 2009 A black error is a common type of error in certain types of digital television Transmission telecommunications transmission , particularly those that use image compression . Its presence in a television image is a telltale sign that 1 the signal is broadcast digitally, as this type of error can not occur in analog signal analog transmission, and 2 that there is a significant amount of signal noise noise , as digital television is designed to tolerate a certain amount of interference. Block errors are usually Error detection detected , but not Error correction corrected , by the receiving device and are commonly displayed as empty black boxes in the television image. Because of how television images are usually compressed, a block error in a single frame often results in black boxes in several subsequent frames. In the worst case, a few block errors per frame could render the video from a television broadcast unviewable. Block errors are most common in digital satellite television , where bad weather or motion of the satellite dish can cause interference outside the broadcaster s control. Block errors can occur at levels of interference where an analog transmission would be fuzzy but still viewable. Thus, block errors are a fine example of the consequences of trade off s in engineering . Although in ideal conditions, digital transmission far exceeds analog transmission in performance, below a certain threshold of signal to noise ratio , digital transmission becomes untenable. DEFAULTSORT Block Error Category Television terminology tv term stub ... more details
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 ... measurements, and reduced by averaging multiple measurements. Systematic error cannot be discovered this way because it always pushes the results in the same direction. If the cause of a systematic error ... more details
Refimprove date December 2009 The error floor is a phenomenon encountered in modern iterated sparse graph code sparse graph based error correcting codes like LDPC codes and turbo codes . When the bit error ratio BER is plotted for conventional codes like Reed Solomon code s under algebraic decoding or for convolutional codes under Viterbi decoder Viterbi decoding , the BER steadily decreases in the form of a curve 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
Orphan date February 2009 In software testing , error guessing is a test method in which test case s used to find Computer bug bug s in Computer program program s are established based on experience in prior testing. The scope of test cases usually rely on the software tester involved, who uses past experience and Intuition knowledge intuition to determine what situations commonly cause software failure, or may cause errors to appear. Typical errors include divide by zero , null pointer s, or invalid Parameter computer programming parameter s. Error guessing has no explicit rules for testing ref cite web title What is Error Guessing? publisher Software Testing Mentor url http www.softwaretestingmentor.com types of testing error guessing.php ref test cases can be designed depending on the situation, either drawing from functional documents or when an unexpected undocumented error is found while testing operations. References http www.istqb.org download attachments 2326555 ISTQB Glossary of Testing Terms 2 1.pdf ISTQB Current Glossary pdf Reflist DEFAULTSORT Error Guessing Category Software testing computer stub nl Error Guessing ... more details
In telecommunication , a burst error or error burst is a contiguous sequence of symbols, received over a data transmission channel communications channel , such that the first and last symbols are in error and there exists no contiguous subsequence of m correctly received symbols within the error burst . ref citation title Federal Standard 1037C url http www.its.bldrdoc.gov fs 1037 fs 1037c.htm ref The integer parameter m is referred to as the guard band of the error burst. The last symbol in a burst and the first symbol in the following burst are accordingly separated by m correct bits or more. The parameter m should be specified when describing an error burst. Channel model The Gilbert Elliott model is a simple channel model introduced by Edgar Gilbert ref citation last Gilbert first E. N. authorlink Edgar Gilbert title Capacity of a burst noise channel journal Bell System Technical Journal volume 39 year 1960 pages 1253 1265 . ref and E. O. Elliott ref citation last Elliott first E. O. title Estimates of error rates for codes on burst noise channels journal Bell System Technical Journal volume 42 year 1963 pages 1977 1997 . ref widely used for describing burst error patterns in transmission channels, that enables simulations of the digital error performance of communications links. It is based on a Markov chain with two states G for good or gap and B for bad or burst . In state G the probability of transmitting a bit correctly is k and in state B it is h . Usually ref Lemmon, J.J. Wireless link statistical bit error model. US National Telecommunications and Information Administration NTIA Report 02 394 2002 ref , it is assumed that k 1 and Gilbert also assumed that h 0.5. References references External links http www.net.t labs.tu berlin.de papers HH GEMPLRTSI 08.pdf http bnrg.cs.berkeley.edu adj publications paper files winet01.pdf http www.wirelesscommunication.nl reference chaptr03 fading gilbert.htm FS1037C MS188 Category Markov ... 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 Category Programming language theory compu prog stub bg de Logischer Fehler fa it Errore di semantica ... more details
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