The state of being accurate; freedom from mistakes, this exemption arising from carefulness; exact conformity to truth, or to a rule or model; precision; exactness; nicety; correctness; as, the value of testimony depends on its accuracy.
(IEEE) (1) A qualitative assessment of correctness or freedom from error. (2) A quantitative measure of the magnitude of error. Contrast with precision. (CDRH) (3) The measure of an instrument's capability to approach a true or absolute value. It is a function of precision and bias. See: bias, precision, calibration.
Represents how close the actual position of a nanopositioner is to the theoretical position to which it is expected to move. It is affected (or determined) by linearity error, hysteresis, abbe error, scale factor error and positioning noise, etc.
In firearms using single projectiles at a given distance, is the measure of the dispersion of the group of projectiles fired. The optimum would be one hole no larger in diameter than a single projectile.
Closeness of agreement between the result of a measurement and the (conventional) true value of the measurement. Note 1. Use of the term precision for accuracy should be avoided. Note 2. True value is an ideal concept and, in general, cannot be known exactly. (Metrology, 1984)
The degree with which an instrument measures a variable in terms of an accepted standard value or true value; usually measured in terms of inaccuracy but expressed as accuracy; often expressed as a percentage of full-scale range.
Conformity with a standard or correctness in measurement. Accuracy relates to the quality of a result and is distinguished from precision which relates to the quality of the operation by which the result is obtained.
Quantity referring to the differences between the mean of a set of results or an individual result and the value which is accepted as the true or correct value for the quantity measured. Gold, Loening, McNaught and Sehmi, 1987 RT precision.
Precision in the measurement of quantities and in the statement of physical characteristics. Accuracy is typically expressed in terms of error as a percentage of the specified value (e.g., 10 volts ± 1%), as a percentage of a range (e.g., 2% of full scale), as parts (e.g., 100 parts per million) or with absolute tolerances (e.g., 6.7kg ± 0.1kg).
(of a test). The proportion of correctly classified patients based on the test and its threshold. The proportion of true positive classifications plus the proportion of true negative classifications. [See prevalence, sensitivity, specificity
The difference between a set of representative values and the actual values. The accuracy of a point location would be the difference between the point's coordinates in the GIS and the coordinates accepted as existing in the real world.
Refers to how well your measurement of an object or phenomenon reflects its actual state. For example, it is important to have an accurate measurement of your feet in order to select well-fitting shoes. (See also Bias, Precision and Validity.)
The degree to which an indicated value matches the actual value of a measured variable. In instrumentation, the ratio of the error to the full-scale output, usually measured as + ___ percent of full-scale output.
condition or quality, of an action, of being correct, true, or exact. Accuracy is typically a judgment by a verbal community about an action, not a property of the action itself. Accuracy differs from effectiveness. Accuracy also forms one of the defining properties of fluency.
This is the deviation between the actual position and the theoretical position of each bit edge. The base accuracy of an encoder is traceable to the encoding disc. Accuracy is different from and is not directly related to resolution.
A paternity test is considered accurate when proper procedures are followed to ensure that the results of the test are correct. At GeneSys, each sample is independently tested two times and the data are compared for consistency before reporting. The test results, reported as allele sizes, are objective measurements and are reliable, reproducible, and accurate.
A measure of the difference between expected position and actual position of a motor or mechanical system. Motor accuracy is usually specified as an angle representing the maximum deviation from expected position.
A measure of the precision with which genetic merit is predicted. Accuracy ranges from .01 (low) if no information is available, to .99 (high) if there is a large amount of performance information on the individual and its relatives. It is an expression of the reliability of the EPD. Accuracies indicate the level of confidence that the predicted EPD is near the true genetic potential of that animal. Accuracies are not available at this time.
The degree to which a measurement, or an estimate based on measurements, represents the true value of the attribute that is being measured. (See also Precision and Validity which are the two components of "Accuracy")
Accuracy normally refers to conformity of an indicated value to an accepted standard value. There is no indication in switch products; thus, instead, the term repeatability is used as the key performance measure.
A measure of how well one set of data matches another, particularly how well a set of predictions match the actual measures. Accuracy is not a simple subject, it is not the opposite of error and there are many ways to calculate accuracy with widely different results. The typical calculation of accuracy is 1-(abs(Predicted-Actual)/Actual), however this calculation breaks down if the Actual is zero (0). Another example of an accuracy calculation is "Relative Accuracy" which is 1-(abs(Predicted-Actual)/(Range of Actual).
A measure of the similarity of an instrument reading to the actual value for that reading. The accuracy of temperature measurement indicators on thermal imagers is affected by emissivity, the distance from the object, the angle of the object and a number of other factors.
1. If applied to paper maps or map databases, degree of conformity with a standard if accepted value. Accuracy relates to the quality of a result and is distinguished from precision. 2. If applied to data collection devices such as digitizers, degree of obtaining the correct value.
The degree of agreement between an observed value and an accepted reference value. Accuracy includes a combination of random error (precision) and systematic error (bias), components which are due to sampling and analytical operations (NELAC, 2001). Note: Because the true toxicity (unlike, for example, mass) of a material cannot be determined this term is generally not considered applicable to toxicity testing. Consequently "true" values for laboratory evaluation studies are typically mean or median values of participating labs.
A measure of closeness of agreement between a test result and an accepted reference value. EXAMPLE: If you have a standardized reference material at a known value (such as 180 mg/dl of cholesterol), accuracy measures how close the result of the test you are using will get to the known value. You may have a test that is very precise yet very inaccurate, which would be the case if your device measures 180 mg/dl of cholesterol reproducibly as 240 mg/dl.
is the degree to which information on a map or in a digital database matches true or accepted values. Accuracy is an issue pertaining to the quality of data and the number of errors contained in a dataset or map. In discussing a GIS database, it is possible to consider horizontal and vertical accuracy with respect to geographic position, as well as attribute, conceptual, and logical accuracy. The effect of inaccuracy and error on a GIS solution is the subject of sensitivity analysis . Accuracy, or error, is distinguished from precision , which concerns the level of measurement or detail of data in a database.
The quality of closeness to a specified value under stated reference conditions. Accuracy is quantitatively expresses by uncertainty. Accuracy, intrinsic: The limit of the accuracy of an instrument when used under reference conditions. Accuracy is expresses in percentage of the fiducial value. This concept of accuracy is concerned with the intrinsic qualities of the instrument as opposed to the variation in indication that may arise when the instrument is used under conditions other than the reference conditions. Intrinsic accuracy is the uncertainty of the instrument in the "as received" condition, without the applications of corrections from a chart, curve or tabulation.Accuracy, rated (class): The assigned classification, which represents the value of uncertainty that the intrinsic accuracy of the instrument will not exceed.
The closeness of approach of a measured dimension to the "true" or nominal value specified. Since both the "true" value and the measured dimension can only be approximated within some tolerance limits rather than exactly determined, the most probable value derived, examined for sources of error, is used as the "true" value. See Precision.
the degree to which a measurement (e.g., the mean estimate of a treatment effect) is true or correct. An estimate can be accurate, yet not be precise, if it is based upon an unbiased method that provides observations having great variation (i.e., not close in magnitude to each other). (Contrast with precision.)
The term accuracy refers to how close we are to the nominal value. In the past we have used this term to indicate error in a measurement device. For instance, the accuracy of a standard cell is plus or minus 0.01 percent. Use of the word accuracy in this sense is incorrect because what we mean is the inaccuracy or error is plus or minus 0.01 percent. However, this is still a common method of describing accuracy?s. To remedy this practice, the National Bureau of Standards has dropped the term accuracy, when used in this respect, and uses instead the term "uncertainty."
Accuracy is the degree of error between the intended, specified, or nominal property value and actual value. Typically used to define the performance envelope of a production lot of parts about the specified nominal. Normally used to relate single-event performance of multiple parts. Compare to PRECISION.
With regard to spatial data, the degree of conformity with a standard, whether absolute or relative. Accuracy relates to the quality of the result so that higher accuracy implies that a measurement is nearer the truth.
The degree of uncertainty with which a measured value agrees with the ideal values. Accuracy class of instrument transformers are defined by the requirements of ANSI standard number C57.13. Standard metering accuracy classes are 0.3, 0.6 and 1.2
An expression describing the ability of a measuring instrument to show the true value of a measured quantity. It is generally expressed as the magnitude of the total error expected in the measurement. It is usually given as a percent of full scale reading of the measuring instrument.
The freedom from mistake or error: correctness. The degree of conformity to some recognized standard value. For purposes of the ZIMS Project, accurate data captured from user input, system interfaces or external data feeds is properly validated.
A criterion used in evaluating the quality of information. Accuracy measures the degree to which information sources are free from mistakes and errors. An encyclopedia which said that the Oakland Raiders won the Super Bowl in 2000 would be giving inaccurate information.
The difference between a value appearing on the website and the actual value of that item. Data values may be affected by rounding and estimation, as well as by other quality issues. The dataset information (metadata) will give full details. Note that values may be published to a high resolution, such as two decimal places, without being accurate to that level.
The degree of conformity of the indicated (measured) value to the true value. The accuracy of a venturi based on empirical data varies with the diameter and method of construction. By individual calibration the accuracy can be +/- 1/2%.
Degree of conformance of a value to a recognized, accepted standard value. Accuracy is expressed as the maximum positive and negative deviation from the standard for specific conditions, usually expressed as the inaccuracy as a percent of the value, instrument range, or full-scale value. It includes causes of inaccuracy, including linearity, repeatability and hysteresis.
The degree of conformance between the estimated or measured position, time, and/or velocity of a GPS receiver and its true time, position, and/or velocity as compared with a constant standard. Radionavigation system accuracy is usually presented as a statistical measure of system error and is characterized as follows: Predictable - The accuracy of a radionavigation system's position solution with respect to the charted solution. Both the position solution and the chart must be based upon the same geodetic datum. Repeatable - The accuracy with which a user can return to a position whose coordinates have been measured at a previous time with the same navigation system. Relative - The accuracy with which a user can measure position relative to that of another user of the same navigation system at the same time.
degree of conformity with a standard. Accuracy relates to the quality of a result, and is distinguished from precision, which relates to the quality of the operation by which the result is obtained. see Accuracy and Precision for further information.
Compare with precision and trueness. Accuracy is the correctness of a single measurement. The accuracy of a measurement is assessed by comparing the measurement with the true or accepted value, based on evidence independent of the measurement. The closeness of an average to a true value is referred to as "trueness".
Absolute accuracy is defined as the expected maximum error in the geographical position as computed by the DGPS user equipment within some specified statistical limit. For DGPS systems the limit is usually the horizontal two dimensional error measure called 2 drms (twice the root mean square error). For the Canadian DGPS system, the error limit is 95%, which is the minimum 2 drms value for bivariate normal error distribution. The position accuracy of the DGPS Service will be 10 meters, 95% of the time; or better in all specified coverage areas (assuming the full 24 GPS satellite constellation and a HDOP 2.3).
A measure of the closeness of agreement of a measured test result obtained by the analytical method to its theoretical true (or accepted reference) value. This is relevant only for calibration-curve based applications where a purified or relative reference standard material is available to quantify the analyte levels in test samples.
The difference between the "measured" and "true" values. The degree of statistical agreement (usually at the 95% confidence level) between a measured value and the true value, or the certainty or "sureness" with which a measured value is known.
The deviation between actual value and the expected, ideal value. Absolute accuracy specifies the degree of accuracy that exists in comparison to primary or secondary standards under all specified operating conditions. Typical accuracy is sometimes called relative or nominal accuracy. It assumes that a fixed set of operating conditions exist, and that the instrument parameters statistically average to provide a typical operating accuracy throughout its measuring range.
The closeness to the truth of measurement data or station coordinates. Accuracy can only be determined by a comparison against an independent determination or measurement of the data or coordinates. "Check" surveys are often carried out independently of the main survey of an area to detect inaccuracies in the station coordinates.
1. The degree to which a measured value is similar to an actual value. 2. The extent to which vision sensors can correctly measure and obtain a true value of a feature. A combination of imager resolution, pixel resolution and field of view is used to describe the match level of an inspection.
(Measurement and Inspection) The difference between indicated value and actual value, at room temperature. In most cases, the accuracy is comprised of two main sources of error: the resolution and the linearity.
A statement that is used to define the largest allowable error in a device or system. It is an indication of how close measured values are to true values. It can be expressed in both measured units and in percentages.
The degree of agreement of a measurement (X) with an accepted reference or true value (T); usually expressed as the difference between the two values (X – T), or the difference as a percentage of the reference or true value (100[X – T]/T), and sometimes expressed as a ratio (X/T).
(1) In common usage, accuracy is the quality of being true or correct. (2) As a measure of diagnostic performance, accuracy is a measure of how faithfully the information obtained using a medical imaging agent reflects reality or truth as measured by a truth standard or gold standard. Accuracy is the proportion of cases, considering both positive and negative test results, for which the test results are correct (i.e., concordant with the truth standard or gold standard.) Accuracy = (a+d)/N = (TP+TN)/(TP+FP+FN+TN).
Also known as Precision Landing, this is a competition discipline in which the skydiver attempts to land on an established target. At the National level the target is 3 cm in diameter, about the size of a quarter. Accuracy landings of various difficulty, from 20 meters to 2 meters, are required for USPA licenses. See the SIM for details.
A measure of the similarity of an instrument reading to the actual value for that reading. Instrument accuracy is affected by many things -instrument drift, environment, temperature, time, operator expertise, etc.
Accuracy is an important factor in assessing the success of data mining. When applied to data, accuracy refers to the rate of correct values in the data. When applied to models, accuracy refers to the degree of fit between the model and the data. This measures how error-free the model's predictions are. Since accuracy does not include cost information, it is possible for a less accurate model to be more cost-effective. Also see precision.
The accuracy of manufacture and erection is generally in accordance with the appropriate British Standard: BS8110 for structural concrete and BS8297:2000 for precast cladding. Interface tolerances must be agreed at the earliest design stage.
The deviation of the actual dimension from the nominal dimension as described by tolerances. For monorail systems, accuracy is defined as the parallel deviation of the reference surfaces within given tolerances. See Running accuracy and Dimensional accuracy.
Department of Defense parlance for the notion that information has been maintained and transferred in such a way as to be inviolate (the information has been protected from being modified or otherwise corrupted either maliciously or accidentally). Accuracy protects against forgery or tampering.
The degree to which the output signal from a component or system is perceived as replicating the sonic qualities of its input signal. An accurate device reproduces what is on the recording, which may or may not be an accurate representation of the original sound.