Mathematica , a result not published until 1926, but he says nothing about Bernays proving their consistency . ref and Emil Post in 1921, ref Post proves both consistency and completeness of the propositional ... 1967 582ff ref and consistency proofs for arithmetics restricted with respect to the Mathematical ... 1931 . ref cf van Heijenoort s commentary and Herbrand s 1930 On the consistency of arithmetic in van Heijenoort 1967 618ff. ref Stronger logics, such as second order logic , are not complete. A consistency ... proof theory was driven by the desire to provide finitary consistency proofs for all ... cannot prove their own consistency provided that they are in fact consistent . Although consistency ... normalization of the Curry Howard underlying calculus if there is one implies the consistency of the calculus .... Consistency and completeness in arithmetic In theories of arithmetic, such as Peano arithmetic , there is an intricate relationship between the consistency of the theory and its completeness . A theory ... arithmetic . Moreover, G del s second incompleteness theorem shows that the consistency of sufficiently ..., which is a formalized statement of the claim that the theory is indeed consistent. Thus the consistency ... problem Jan ukasiewicz Matiyasevich s theorem consistency Footnotes references References Stephen ... , consistency H.D. Ebbinghaus, J. Flum, W. Thomas, Mathematical Logic Jevons, W.S., 1870, Elementary ... more details
NOTOC wiktionary consistency wikiquote ConsistencyConsistency can refer to Consistency negotiation , the psychological need to be consistent with prior acts and statements Consistency , an 1887 speech by Mark Twain The consistency criterion , a measure of a voting system requiring that where one is elected by all segments of the voters, one must win the election Consistency Theory , an album by 1200 Techniques Consistent histories quantum mechanics Consistent Life Ethic , an ideology stating that life is sacred Consistency, a property of a system of linear equations Consistency system of linear equations Mr. Consistency foaled 1958 , American Thoroughbred racehorse In computer science Consistency database systems Consistency knowledge bases Consistent hashing Consistent heuristic Consistency model In logic Consistency Equiconsistency In statistics See Consistency statistics , which describes Consistent estimator Fisher consistency Consistent test see Statistical hypothesis testing Definition of terms Statistical hypothesis testing See also Constancy disambig cs Konzistence es Consistencia fa fr Coh rence he nl Consistentie ja simple Consistency fi Eheys ... more details
unreferenced date December 2011 Strong consistency is one of the consistency model s used in the domain of the concurrent programming e.g. in distributed shared memory , distributed transactions etc. . The protocol is said to support strong consistency if All accesses are seen by all parallel processes or nodes, processors etc. in the same order sequentially Therefore only one consistent state can be observed, as opposed to weak consistency , where different parallel processes or nodes etc. can perceive variables in different states. Category Consistency models ... more details
Unreferenced date July 2009 PRAM consistency pipelined random access memory also known as FIFO Consistency model consistency , or Central processing unit Processor Consistency model consistency . All Process computing processes see Computer storage memory writes from one process in the order they were issued from the process. Writes from different processes may be seen in a different order on different processes. Only the write order needs to be consistent , thus the name pipelined . PRAM consistency is easy to implement. In effect it says that there are no guarantees about the order in which different processes see writes, except that two or more writes from a single source must arrive in order, as though they were in a pipeline. P1 W x 1 P2 R x 1W x 2 P3 R x 1R x 2 P4 R x 2R x 1 Time Fig A valid sequence of events for PRAM consistency. The above sequence is not valid for Causal consistency because W x 1 and W x 2 are causal, so different processes must read it in the same sequence. DEFAULTSORT Pram Consistency Category Consistency models Category Computing acronyms ... more details
other Consistency disambiguation In negotiation , consistency , or the consistency principle, refers to a negotiator s strong psychological need to be consistent with prior acts and statements. Dr. Robert Cialdini and his research team have conducted extensive research into what Cialdini refers to as the Consistency Principle of Persuasion . Described in his book Influence Science and Practice , this principle states that people live up to what they have publicly said they will do and what they have written down. So Cialdini encourages us to have others write down their commitments as a route to having others live up to their promises. wikiquote Consistency Category Negotiation social psych stub ... more details
Immediate consistency is one of the consistency model s used in the domain of parallel programming , in contrast to eventual consistency . The term immediate refers not to updates not taking any time to perform, but simply to the fact that when an update operation returns to the user with a successful result, the result of that update is immediately visible to all observers. Non replicated distributed data storage systems, or non distributed data storage systems such as traditional centralized databases, tend to provide immediate consistency, as there is only one location at which to update the data, rather than multiple copies also, distributed replicated systems using synchronous replication offer immediate consistency by forcing the user to wait until confirmation of the update has been received or inferred from every replica of the data. Immediate consistency defines only the state of the system with regard to a single update, after the update has been reported to the user as completed it does not define the state of the system that might be observed while an update is in progress e.g., to other users of the system . Therefore, it does not imply sequential consistency or strict consistency , but is not incompatible with them. See also Eventual consistency Two phase commit protocol Paxos algorithm External links http books.couchdb.org relax intro eventual consistency CouchDB book Eventual Consistency http citrusleaf.net clsolutions.html CitrusLeaf case studies http blog.geniedb.com 2010 01 13 eventual consistency A technique for improving upon eventual consistency DEFAULTSORT Immediate Consistency Category Consistency models ... more details
Sequential consistency is one of the consistency model s used in the domain of concurrent programming e.g. in distributed shared memory , distributed transactions , etc. . It was first defined as the property that requires that ... the result of any execution is the same as if the operations of all the processors were executed in some sequential order, and the operations of each individual processor appear in this sequence in the order specified by its program. ref Leslie Lamport , How to Make a Multiprocessor Computer That Correctly Executes Multiprocess Programs , IEEE Trans. Comput. C 28,9 Sept. 1979 , 690 691. ref The system provides sequential consistency if every node of the system sees the write operations on the same memory part page, virtual object, cell, etc. in the same order, although the order may be different from the order as defined by real time as observed by hypothetical external observator or global clock of issuing the operations. The sequential consistency is weaker than strict consistency which would demand that operations are seen in order in which they were actually issued, which is essentially impossible to secure in distributed system as deciding global time is impossible and is the easiest consistency model to understand, since a system preserving that model is behaving in a way expected by an instantaneous system. See also Consistency model Serializability Linearizability References references DEFAULTSORT Sequential Consistency Category Consistency models ja ru ... more details
Unreferenced date December 2009 Orphan date December 2009 Release consistency is one of the consistency model s used in the domain of the concurrent programming e.g. in distributed shared memory , distributed transaction s etc. . Systems of this kind are characterised by the existence of two special synchronisation operations, release and acquire . Before issuing a write to a memory object a node must acquire the object via a special operation, and later release it. Therefore the application that runs within the operation acquire and release constitutes the Mutual exclusion critical region . The system is said to provide release consistency, if all write operations by a certain node are seen by the other nodes after the former releases the object and before the latter acquire it. There are two kinds of coherence protocol s that implement release consistency eager , where all coherence actions are performed on release operations, and lazy , where all coherence actions are delayed until after a subsequent acquire DEFAULTSORT Release Consistency Category Consistency models ... more details
In computer science , consistency models are used in Distributed computing distributed systems like distributed ... follow specific rules. The data consistency model specifies a contract between programmer and system .... ref cite journal author Mark D. Hill title Multiprocessors Should Support Simple Memory Consistency ... 2.707614 ref Verifying sequential consistency is undecidable problem undecidable in general, even ... Consistency on Shared Memory Multiprocessors by Model Checking month August year 2003 journal ... TPDS.2003.1225053 ref Consistency models define rules for the apparent order and visibility of updates ... Design Patterns for Distributed Non Relational Databases quote A consistency model determines rules ... B see the write from client A? Consistency is a continuum with tradeoffs url http static.last.fm johan ... t, client B reads row X from node M The consistency model has to determine whether client B does see the write from client A or not. Types A non exhaustive list of consistency models are causal consistency delta consistency entry consistency eventual consistency fork consistency linearizability also known as strict or atomic consistency one copy serializability PRAM consistency also known as FIFO consistency release consistency sequential consistency serializability vector field consistency weak consistency strong consistency See also Cache coherence Distributed shared memory Non Uniform Memory ... Wallace year 2004 title A Proposal for a UPC Memory Consistency Model v1.0 url http www.gwu.edu upc downloads upcmem.pdf format PDF cite journal last Mosberger first David title Memory Consistency Models ... Gharachorloo title Shared Memory Consistency Models A Tutorial month December year 1996 journal IEEE ... theory of shared memory consistency journal Journal of the ACM year 2004 volume 51 issue 5 pages ... dsm green memcohe.html Consistency Models http www.ietf.org old 2009 proceedings 01mar slides webi ... Journal Parallel computing Category Consistency models Category Transaction processing Interwikies es ... more details
Multiple issues context November 2008 refimprove November 2008 orphan August 2009 The convention of consistency means that same accounting principles should be used for preparing financial statement s for different periods. It enables the management to draw important conclusions regarding the working of the concern over a longer period. It allows a comparison in the performance of different periods. If different accounting procedures and processes are used for preparing financial statements of different years then the results will not be comparable because these will be based on different postulates. The concept of consistency does not mean that no change should be made in accounting procedures. There should always be a scope for improvement but the changes should be notified in the statements. The impact of changes of procedures should be clearly stated. It will enable the readers to analyze information according to new procedures. In the absence of any information regarding the change, it will be presumed that old methods have been used this time also. Whenever, consistency is not followed this fact may be fully disclosed. For example, if a change in the method of charging depreciation is made or a change is made in the method of allocating overhead expenses to different products, a foot note to the financial statements should be given indicating the extent of change. If possible, net monetary effect of these changes should also be given. Consistency may be of three types Vertical consistency Horizontal consistency Third dimensional consistency The vertical consistency is maintained within inter related financial statements of the same period. If a change has been made in dealing with two aspects of the same statement then it will be vertical inconsistency. For example ... it will be a case of horizontal consistency. Third dimensional consistency will arise when financial ..., Ludhiana 141 008 p 2.8 2.9 ref References references DEFAULTSORT Convention Of Consistency Category ... more details
The name weak consistency may be used in two senses. In the first sense, strict and more popular, the weak consistency is one of the consistency model s used in the domain of the concurrent programming e.g. in distributed shared memory , distributed transactions etc. . The protocol is said to support weak consistency if All accesses to synchronization variables are seen by all processes or nodes, processors in the same order sequentially these are synchronization operations. Accesses to critical sections are seen sequentially. All other accesses may be seen in different order on different processes or nodes, processors . The set of both read and write operations in between different synchronization operations is the same in each process. Therefore, there can be no access to synchronization variable if there are pending write operations. And there can not be any new read write operation started if system is performing any synchronization operation. In the second, more general, sense weak consistency may be applied to any consistency model weaker than sequential consistency . The opposite of weak consistency is strong consistency , where parallel processes can observe only one consistent state. References references The original paper on weak ordering M. Dubois, C. Scheurich and F. A. Briggs, Memory Access Buffering in Multiprocessors , in Proceedings of 13th Annual International Symposium on Computer Architecture 14, 2 June 1986 , 434 442. Sarita Adve Sarita V. Adve , Mark D. Hill, Weak ordering a new definition , in Proceedings of the 17th Annual International Symposium on Computer Architecture , http citeseerx.ist.psu.edu viewdoc summary?doi 10.1.1.42.5567 Category Consistency models ru ... more details
In computer vision Photo consistency determines whether a given voxel is occupied. A voxel is considered to be photo consistent when its color appears to be similar to all the cameras that can see it. ref Jianfeng Yin and Jeremy R. Cooperstock, A New Photo Consistency Test for Voxel Coloring, Proceedings of the Second Canadian Conference on Computer and Robot Vision CRV 05 , IEEE ref Most voxel coloring or space carving techniques require using photo consistency as a check condition in Image based modeling and rendering applications. Usage 3D Volumetric Reconstruction. ref Alexander Hornung, and Leif Kobbelt, Robust and Efficient Photo Consistency Estimation for Volumetric 3D Reconstruction, Lecture Notes in Computer Science, Springer Berlin Heidelberg. ref Image registration . ref Zsolt Janko, Dmitry Chetverikov, Photo Consistency Based Registration of an Uncalibrated Image Pair to a 3D Surface Model Using Genetic Algorithm, Proceedings of the 3D Data Processing, Visualization, and Transmission, 2nd International Symposium. ref Multi view reconstruction. ref Sudipta N. Sinha Marc Pollefeys, Multi view Reconstruction using Photo consistency and Exact Silhouette Constraints A Maximum Flow Formulation. ref References Reflist Computer graphics stub Category computer vision Category Stereoscopy ... more details
Delta consistency is one of the consistency model s used in the domain of parallel programming , for example in distributed shared memory , distributed transactions , and Optimistic replication The delta consistency model states that an update will propagate through the system and all replicas will be consistent after a fixed time period . In other words, the result of any read operation is consistent with a read on the original copy of an object except for a short bounded interval after a modification. So basically, if you have an object which is modified, during the short period of time following its modification, the read will not be consistent. Then, after a fixed time period, the modification is propagated and the read will be consistent. Sources Communication Systems The State of the Art IFIP 17th World Computer Congress, Lyman Chapin ed. 2002 Category Consistency models Compu lang stub ar ... more details
In statistics , consistency of procedures such as confidence intervals or hypothesis tests involves their behaviour as the number of items in the data set to which they are applied increases indefinitely. In particular, consistency requires that the outcome of the procedure should identify the underlying truth. ref name Dodge Dodge, Y. 2003 The Oxford Dictionary of Statistical Terms , OUP. ISBN 0 19 920613 9 entries for consistency, constistent estimator, consistent test ref Use of the term in statistics derives from Sir Ronald Fisher in 1922. ref Upton, G. Cook, I. 2006 Oxford Dictionary of Statistics , 2nd Edition, OUP. ISBN 978 0 19 954145 4 ref Use of the terms consistency and consistent in statistics is restricted to cases where essentially the same procedure can be applied to any number of data items. In complicated applications of statistics, there may be several ways in which the number of data items may grow. For example, records for rainfall within an area might increase in three ways records for additional time periods records for additional sites with a fixed area records for extra sites obtained by extending the size of the area. In such cases, the property of consistency may be limited to one or more of the possible ways a sample size can grow. Estimators Main Consistent estimator A consistent estimator is one which, considered as a random variable indexed by the number of items in the data set, Convergence of random variables converges to the value that the estimation procedure is designed to estimate. Main Fisher consistency An estimator that has Fisher consistency is one for which, if the estimator were calculated using the entire population rather than a sample, the true value of the estimated parameter would be obtained. Tests Main Statistical hypothesis testing A Statistical hypothesis testing Definition of terms consistent test is one for which the statistical power power of the test for a fixed untrue hypothesis increases to one as the number of data ... more details
In constraint satisfaction , local consistency conditions are properties of constraint satisfaction problem s related to the consistency of subsets of variables or constraints. Several such conditions exist, the most known being node consistency , arc consistency , and path consistency . Local consistency can be enforced via transformations of the problem called constraint propagation . Local consistency conditions can be grouped into various classes. The original local consistency conditions require ... consistency only requires this condition to be satisfied when the other variable is higher than the ones in the assignment, according to a given order. Relational consistency includes extensions to more .... Every local consistency condition can be enforced by a transformation that changes the problem .... Local consistency The standard local consistency conditions all require that all consistent partial ... variables. Node consistency Node consistency requires that every unary constraint on a variable ..., 4 right math and a constraint math V le 3 math , node consistency would restrict the domain to math ... later stages. Arc consistency Image Arc consistency 1.svg thumb 250px x2 is arc consistent with x3 ... normalized problems Arc consistency can also be defined relative to a specific binary constraint a binary ... such that they satisfy the constraint. This definition of arc consistency is similar to the above ... considers only a specific one. Image Arc consistency 2.svg thumb 250px Arc consistency enforced ... arc consistency it removes, from the domain of the variable, every value that does not correspond ... with math x 2 math but the algorithm reduces the domain of math x 2 math , arc consistency ... By complexity simplistic algorithm would cycle over the pairs of variables, enforcing arc consistency ... a constraint and enforces arc consistency if this operation may have produced a violation of arc consistency over another constraint, it places it back in the set of constraints to analyze. This way ... more details
Causal consistency is one of the consistency model s used in the domain of the concurrent programming e.g. in distributed shared memory , distributed transactions etc . A system provides causal consistency if memory operations that potentially are causally related are seen by every node of the system in the same order. Concurrent writes i.e. ones that are not causally related may be seen in different order by different nodes. This is weaker than sequential consistency , which requires that all nodes see all writes in the same order, but is stronger than PRAM consistency , which requires only writes done by a single node to be seen in the same order from every other node. When a node performs a read followed later by a write, even on a different variable, the first operation is said to be causally ordered before the second, because the value stored by the write may have been dependent upon the result of the read. Similarly, a read operation is causally ordered after the earlier write on the same variable that stored the data retrieved by the read. Also, even two write operations performed by the same node are defined to be causally ordered, in the order they were performed. Intuitively, after writing value v into variable x , a node knows that a read of x would give v , so a later write could be said to be potentially causally related to the earlier one. Finally, we force this causal order to be transitive that is, we say that if operation A is causally ordered before B, and B is ordered before C, A is ordered before C. Operations that are not causally related, even through other operations, are said to be concurrent. External links http citeseerx.ist.psu.edu viewdoc summary?doi 10.1.1.50.3356 Causal Memory Definitions, Implementation and Programming 1994 , a paper from the authors of the definition Category Consistency models ru ... more details
Thoroughbred racehorse infobox horsename Mr. Consistency image caption sire Alibhai horse Alibhai grandsire Hyperion horse Hyperion dam Invariable damsire Thumbs Up sex Stallion horse Stallion foaled 1958 country United States colour Bay horse Bay breeder Travis M. Kerr owner 1 Travis M. Kerr Kerr Stable Kerr Stable 2 Ann Peppers trainer James I. Nazworthy record 77 11 17 13 earnings United States dollar US 416,360 race California Derby 1961 br Del Mar Handicap 1963 br Santa Anita Handicap 1964 br San Juan Capistrano Handicap 1964 br San Marcos Stakes San Marcos Handicap 1964 br Frank E. Kilroe Mile Handicap Arcadia Handicap 1964 awards honours updated Mr. Consistency foaled 1958 in Kentucky was an American Thoroughbred Horse racing racehorse who was a multiple Graded stakes race stakes winner including the Santa Anita Handicap , California California s richest race and most important for older horses. ref http news.google.ca newspapers?id HLpSAAAAIBAJ&sjid Bn0DAAAAIBAJ&pg 5289,1310875&dq mr consistency santa anita handicap&hl en St. Petersburg Times, February 23, 1964 ref He was bred and raced by Travis M. Kerr , best known as the owner of National Museum of Racing and Hall of Fame Hall of Fame inductee Round Table horse Round Table . He was trained by James I. Nazworthy Jim Nazworthy . Not very sound as a two year old, Mr. Consistency won just once in eleven starts. At age three his only signicant win came in the California Derby at Golden Gate Fields ref http news.google.ca newspapers?id jRAwAAAAIBAJ&sjid OhEEAAAAIBAJ&pg 6041,1496607&dq mr consistency kerr&hl en The Milwaukee ... to get out of horse racing and Mr. Consistency was purchased by Mrs. Ann Peppers at the Kerr Stable ... Mr. Consistency began to develop as a top runner, winning the Del Mar Handicap and running second ... and the Frank E. Kilroe Mile Handicap Arcadia Handicap Mr. Consistency was not successful as a sire . References reflist http www.pedigreequery.com mr consistency Mr. Consistency s pedigree and partial ... more details
Unreferenced date December 2009 Infobox Album See Wikipedia WikiProject Albums Name Consistency Theory Type Album Artist 1200 Techniques Cover 1200 Techniques Consistency Theory.jpg Released January 9, 2004 Recorded ? Genre Hip hop music Hip hop Length 65 11 Label Rubber Sony Records Sony Producer DJ Peril Reviews Last album Choose One br 2002 This album Consistency Theory br 2004 Next album Consistency Theory is the second album from Melbourne, Australia Hip hop music hip hop group 1200 Techniques . Released in 2004, it sees the group moving away from the diverse influences of their first album, to a more straightforward, arguably commercial Hip hop music hip hop sound. The commercial approach is also reflected in the CD artwork, which incorporates thematic elements more reminiscent of the group s American counterparts. Track listing Kem s Theme B boy Shit Eye of the Storm Knock Knock featuring Koolism George the Gangsta Skit The Word featuring Krondon Where Ur At Seduction is Evil She s Hot Looking Back Nothin but Love featuring Motion Man Welcome Aboard Takin U Back Feel the Music featuring Maya Jupiter Robbo Skit 2 Haterade featuring Rodney P & Ken Hell Fork in the Road featuring Rashad Haughton Consistency Theory featuring Kristin U Can Make It Got 2 Survive Category 1200 Techniques albums Category 2004 albums Category English language albums 2000s hiphop album stub ... more details
Data consistency summarizes the validity, accuracy, usability and integrity of related data between applications ... of other users or processes. Data Consistency problems may arise at any time but are frequently ... of the original data. Various kinds of data consistency have been identified. These include Application Consistency , Transaction Consistency and Point in Time PiT Consistency . Point in time consistency ... consistency is an important property of backup files and a critical objective of software that creates ... in time consistency can be illustrated with what would happen if a backup were made without it. Assume ... copies from the beginning to the end of the large file s and doesn t consider data consistency and at the time ... consistency ensures that the backup is a snapshot of how the entire database looked at a single ... written. Disk caching systems Point in time consistency is also relevant to computer disk subsystems ... such that they can be done faster by minimizing the time spent moving disk heads. Data consistency ... in time consistency guarantees that in the event of an unexpected shutdown, the four elements would ... that they are written flushed to the disk at the next available opportunity. Transaction Consistency ... or database updates. Transaction consistency is also frequently referred to as atomicity . A good example of the importance of transaction consistency is a database that handles the transfer of money ... in place to correct this, the system can be said to lack transaction consistency .... Both of these scenarios keep the balance in check. Transaction consistency ensures just ... or roll back the portion of any incomplete transactions that are found. Application Consistency Application software Application Consistency is similar to Transaction consistency, but instead of data consistency within the scope of a single transaction, data must be consistent within the confines ... dc01.html Data Consistency Explained, by Recovery Specialties Category Computer data ru ... more details
Eventual consistency is one of the consistency model s used in the domain of parallel programming , for example in distributed shared memory , distributed transactions , and optimistic replication , ref W. Vogels. http queue.acm.org detail.cfm?id 1466448 Eventually Consistent . ACM Queue vol. 6, no. 6, December 2008. ref ref name Bayou D. B. Terry, et. al. http doi.acm.org 10.1145 224056.224070 Managing update conflicts in Bayou, a weakly connected replicated storage system ACM SOSP, December 1995. ref it means that given a sufficiently long period of time over which no changes are sent, all updates can be expected to propagate eventually through the system and all the replicas will be consistent . While some authors use that definition e.g. Vogels , others prefer a stronger definition that requires good things to happen even in the presence of continuing updates, reconfigurations, or failures. In the Terry et al. work referenced above, eventual consistency means that for a given accepted update and a given replica, eventually, either the update reaches the replica, or the replica retires from service. In database terminology, this is known as BASE B asically A vailable, S oft state, E ventual consistency , as opposed to the database concept of ACID . ref D. Pritchett http queue.acm.org detail.cfm?id 1394128 . ACM Queue vol. 6, no. 3, July 28, 2008. ref Conflict resolution As the consistency achieved is eventual , the conflicts have to be resolved. There are three types of resolution ref name Bayou ref name Conflict cite web accessdate 2011 03 23 author Olivier Mallassi date ... levels of consistency that can be reached. Apache Cassandra uses three levels ref cite web accessdate ... Talks title Let s play with Cassandra Part 1 3 quote Cassandra defines different levels of consistency ... and delete Immediate consistency Optimistic replication References Reflist Interwikies DEFAULTSORT Eventual Consistency Categories Category Consistency models Compu lang stub de Eventual consistency ... more details
In statistics and research , internal consistency is typically a measure based on the correlation s between different items on the same test or the same subscale on a larger test . It measures whether several items that propose to measure the same general construct produce similar scores. For example, if a respondent expressed agreement with the statements I like to ride bicycles and I ve enjoyed riding bicycles in the past , and disagreement with the statement I hate bicycles , this would be indicative of good internal consistency of the test. Internal consistency is usually measured with Cronbach s alpha , a statistic calculated from the pairwise correlations between items. Internal consistency ranges between zero and one. A commonly accepted rule of thumb for describing internal consistency is as follows ref George, D., & Mallery, P. 2003 . SPSS for Windows step by step A simple guide and reference. 11.0 update 4th ed. . Boston Allyn & Bacon. ref class wikitable Cronbach s alpha Internal consistency .9 Excellent .9 .8 Good .8 .7 Acceptable .7 .6 Questionable .6 .5 Poor .5 Unacceptable Very high reliabilities 0.95 or higher are not necessarily desirable, as this indicates that the items may be entirely redundant Citation needed date February 2011 . The goal in designing a reliable instrument is for scores on similar items to be related internally consistent , but for each to contribute some unique information as well. An alternative way of thinking about internal consistency, however, is that it is the extent to which all of the items of a test measure the same latent variable. The advantage of this perspective over the notion of a high average correlation among ... consistency are reviewed by Revelle & Zinbarg 2009 . ref Revelle, W., Zinbarg, R. 2009 Coefficients .... http dx.doi.org 10.1007 s11336 008 9102 z ref See also Cronbach s alpha Consistency Reliability statistics ... DEFAULTSORT Internal Consistency Category Comparison of assessments Category Epidemiology ... more details
In quantum chemistry , size consistency or strict separability is a property that guarantees the consistency of the energy behavior when interaction between the involved molecular system is nullified for example, by distance . Let A and B be two non interacting systems. If a given theory for the evaluation of the energy is size consistent, then the energy of the supersystem A B is equal to the sum of the energy of A plus the energy of B taken by themselves math E A B E A E B math . This property is of particular importance to obtain correctly behaving dissociation curves. Others have more recently argued that the entire potential energy surface should be well defined ref cite book first P. R. last Taylor title Lecture Notes in Quantum Chemistry European Summer School publisher Springer Verlag location Berlin year 1994 pages 125 202 ref . Of the common quantum mechanical methods Hartree Fock , coupled cluster , many body perturbation theory quantum mechanics perturbation theory to any order , and full configuration interaction CI are size consistent. A major drawback of truncated CI is that it is not size consistent and that the quality of the description decreases with increasing size of the system. ref cite book last1 Szabo first1 Attila first2 Neil last2 Ostlund title Modern Quantum Chemistry publisher Dover date 1982 isbn 0029497108 ref The error in CISD calculations can be corrected with e.g. quadratic configuration interaction . Sometimes numerical errors can cause a method that is formally size consistent to behave in a non size consistent manner ref Cite journal last1 Van Dam first1 Huub last2 Van Lenthe first2 Joop last3 Pulay first3 Peter title The size consistency of multi reference M ller Plesset perturbation theory journal Molecular Physics volume 93 pages 431 year 1998 doi 10.1080 002689798169122 ref . Size extensivity , on the other hand, is a more mathematically formal characteristic which refers to the correct linear scaling of a method with the number ... more details
In statistics , Fisher consistency , named after Ronald Fisher , is a desirable property of an estimation theory estimator asserting that if the estimator were calculated using the entire statistical population population rather than a sample statistics sample , the true value of the estimated parameter would be obtained. ref cite journal last Fisher first R.A. authorlink Ronald Fisher journal Philosophical Transactions of the Royal Society of London. Series A, Containing Papers of a Mathematical or Physical Character title On the mathematical foundations of theoretical statistics volume 222 year 1922 pages 309 368 url http digital.library.adelaide.edu.au dspace handle 2440 15172 doi 10.1098 rsta.1922.0009 jstor 91208 jfm 48.1280.02 issue 594 604 ref Definition Suppose we have a sample statistics statistical sample X sub 1 sub , ..., X sub n sub where each X sub i sub follows a cumulative distribution F sub sub which depends on an unknown parameter . If an estimator of based on the sample can be represented as a functional mathematics functional of the empirical distribution function F sub n sub math hat theta T hat F n ,, math the estimator is said to be Fisher consistent if math T F theta theta , . math ref Cox, D.R., Hinkley D.V. 1974 Theoretical Statistics , Chapman and Hall, ISBN 0 412 12420 3. defined on p287 ref As long as the X sub i sub are exchangeable random variables ... functions F sub n sub converge pointwise to F sub sub , allowing us to express Fisher consistency ... Z sub i sub . Thus we have Fisher consistency if T p sub 1 sub , ..., p sub m sub . Suppose ... sum i 1 n mu mu, math so we have Fisher consistency. Role in maximum likelihood estimation Maximising ... library glossary bldef fisher consistency.htm ref Relationship to asymptotic consistency and unbiasedness The term consistency in statistics usually refers to an estimator that is consistent estimator asymptotically consistent . Fisher consistency and asymptotic consistency are distinct ... more details
A voting system is consistent if, when the electorate is divided arbitrarily into two or more parts and separate elections in each part result in the same choice being selected, an election of the entire electorate also selects that alternative. Smith ref Smith calls this property separability and Woodall ref Woodall calls it convexity . It has been proven a preferential voting system is consistent if and only if it is a positional voting system . ref Young Borda count is an example of this. The failure of the consistency criterion can be seen as an example of Simpson s paradox . References note Smith John H Smith mathematician John H Smith , Aggregation of preferences with variable electorate , Econometrica , Vol. 41 1973 , pp. 1027&ndash 1041. note Woodall Douglas R. Woodall D. R. Woodall , http www.votingmatters.org.uk ISSUE3 P5.HTM Properties of preferential election rules , Voting matters , Issue 3 December 1994 , pp. 8&ndash 15. note Young Peyton Young H. P. Young , Social Choice Scoring Functions , SIAM Journal on Applied Mathematics Vol. 28, No. 4 1975 , pp. 824&ndash 838. Category Voting system criteria ... more details
about the property which keeps a consistency in financial risk in time the property in game theory dynamic inconsistency Time consistency is a property in financial risk related to dynamic risk measure s. The purpose of the time consistent property is to categorize the risk measure s which satisfy the condition that if portfolio A is more risky than portfolio B at some time in the future, then it is guaranteed to be more risky at any time prior to that point. This is an important property since if it were not to hold then there is an event with probability of occurring greater than 0 such that B is riskier than A at time math t math although it is certain that A is riskier than B at time math t 1 math . As the name suggests a time inconsistent risk measure can lead to inconsistent behavior in financial risk management . Mathematical definition A dynamic risk measure math left rho t right t 0 T 1 math on math L 0 mathcal F T math is time consistent if math forall X, Y in L 0 mathcal F T math and math t in 0,1,...,T 2 rho t 1 X geq rho t 1 Y math implies math rho t X geq rho t Y math . ref name composition cite journal last Cheridito first Patrick last2 Stadje first2 Mitja year 2008 month October title Time inconsistency of VaR and time consistent alternatives url http www.princeton.edu dito papers timeincVaR Oct08.pdf accessdate November 29, 2010 format pdf ref Equivalent definitions Equality For all math t in 0,1,...,T 2 rho t 1 X rho t 1 Y Rightarrow rho t X rho t Y math Recursive For all math t in 0,1,...,T 2 rho t X rho t rho t 1 X math Acceptance Set For all math t in 0,1,...,T 2 A t A t,t 1 A t 1 math where math A t math is the time math t math acceptance set and math A t,t 1 A t cap L p mathcal F t 1 math ref cite journal last Acciaio first Beatrice last2 Penner first2 Irina date February 22, 2010 title Dynamic risk measures url http wws.mathematik.hu berlin.de penner ... Dynamic convex risk measures time consistency, prudence, and sustainability url http wws.mathematik.hu ... more details
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