Marzullo's Algorithm
   HOME
*





Marzullo's Algorithm
Marzullo's algorithm, invented by Keith Marzullo for his Ph.D. dissertation in 1984, is an agreement algorithm used to select sources for estimating accurate time from a number of noisy time sources. A refined version of it, renamed the "intersection algorithm", forms part of the modern Network Time Protocol. Marzullo's algorithm is also used to compute the relaxed intersection of n boxes (or more generally ''n'' subsets of R''n''), as required by several robust set estimation methods. Purpose Marzullo's algorithm is efficient in terms of time for producing an optimal value from a set of estimates with confidence intervals where the actual value may be outside the confidence interval for some sources. In this case the best estimate is taken to be the smallest interval consistent with the largest number of sources. If we have the estimates 10 ± 2, 12 ± 1 and 11 ± 1 then these intervals are ,12 1,13and 0,12which intersect to form 1,12or 11.5& ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Keith Marzullo
Keith Marzullo is the inventor of Marzullo's algorithm, which is part of the basis of the Network Time Protocol and the Windows Time Service. On August 1, 2016 he became the Dean of the University of Maryland College of Information Studies after serving as the Director of the NITRD National Coordination Office. Prior to this he was a Professor in the Department of Computer Science and Engineering at University of California, San Diego. In 2011 he was inducted as a Fellow of the Association for Computing Machinery The Association for Computing Machinery (ACM) is a US-based international learned society for computing. It was founded in 1947 and is the world's largest scientific and educational computing society. The ACM is a non-profit professional member .... Research *RAMP (Reliable Adaptive Multipath Networks) *GriPhyN (Master-worker computation in a wide-area network) *MURI (Dependent failure models & Collaborative backup for withstanding network catastrophes) *Mobility ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Marzullo Example-2
Marzullo is a family name of Italian origin. Notable people with the name include: * Frank Marzullo, American meteorologist * Gianluca Marzullo, Italian-German footballer * Gigi Marzullo, Italian journalist * Keith Marzullo, American computer scientist See also * Marzullo's algorithm Marzullo's algorithm, invented by Keith Marzullo for his Ph.D. dissertation in 1984, is an agreement algorithm used to select sources for estimating accurate time from a number of noisy time sources. A refined version of it, renamed the "intersect ... {{surname, Marzullo Italian-language surnames ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Big O Notation
Big ''O'' notation is a mathematical notation that describes the limiting behavior of a function when the argument tends towards a particular value or infinity. Big O is a member of a family of notations invented by Paul Bachmann, Edmund Landau, and others, collectively called Bachmann–Landau notation or asymptotic notation. The letter O was chosen by Bachmann to stand for ''Ordnung'', meaning the order of approximation. In computer science, big O notation is used to classify algorithms according to how their run time or space requirements grow as the input size grows. In analytic number theory, big O notation is often used to express a bound on the difference between an arithmetical function and a better understood approximation; a famous example of such a difference is the remainder term in the prime number theorem. Big O notation is also used in many other fields to provide similar estimates. Big O notation characterizes functions according to their growth rates: d ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Asymptotic
In analytic geometry, an asymptote () of a curve is a line such that the distance between the curve and the line approaches zero as one or both of the ''x'' or ''y'' coordinates tends to infinity. In projective geometry and related contexts, an asymptote of a curve is a line which is tangent to the curve at a point at infinity. The word asymptote is derived from the Greek ἀσύμπτωτος (''asumptōtos'') which means "not falling together", from ἀ priv. + σύν "together" + πτωτ-ός "fallen". The term was introduced by Apollonius of Perga in his work on conic sections, but in contrast to its modern meaning, he used it to mean any line that does not intersect the given curve. There are three kinds of asymptotes: ''horizontal'', ''vertical'' and ''oblique''. For curves given by the graph of a function , horizontal asymptotes are horizontal lines that the graph of the function approaches as ''x'' tends to Vertical asymptotes are vertical lines near which the fu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Sorting Algorithm
In computer science, a sorting algorithm is an algorithm that puts elements of a List (computing), list into an Total order, order. The most frequently used orders are numerical order and lexicographical order, and either ascending or descending. Efficient sorting is important for optimizing the Algorithmic efficiency, efficiency of other algorithms (such as search algorithm, search and merge algorithm, merge algorithms) that require input data to be in sorted lists. Sorting is also often useful for Canonicalization, canonicalizing data and for producing human-readable output. Formally, the output of any sorting algorithm must satisfy two conditions: # The output is in monotonic order (each element is no smaller/larger than the previous element, according to the required order). # The output is a permutation (a reordering, yet retaining all of the original elements) of the input. For optimum efficiency, the input data should be stored in a data structure which allows random access ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Tuple
In mathematics, a tuple is a finite ordered list (sequence) of elements. An -tuple is a sequence (or ordered list) of elements, where is a non-negative integer. There is only one 0-tuple, referred to as ''the empty tuple''. An -tuple is defined inductively using the construction of an ordered pair. Mathematicians usually write tuples by listing the elements within parentheses "" and separated by a comma and a space; for example, denotes a 5-tuple. Sometimes other symbols are used to surround the elements, such as square brackets "nbsp; or angle brackets "⟨ ⟩". Braces "" are used to specify arrays in some programming languages but not in mathematical expressions, as they are the standard notation for sets. The term ''tuple'' can often occur when discussing other mathematical objects, such as vectors. In computer science, tuples come in many forms. Most typed functional programming languages implement tuples directly as product types, tightly associated with algebr ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Probabilistic Model
A statistical model is a mathematical model that embodies a set of statistical assumptions concerning the generation of sample data (and similar data from a larger population). A statistical model represents, often in considerably idealized form, the data-generating process. A statistical model is usually specified as a mathematical relationship between one or more random variables and other non-random variables. As such, a statistical model is "a formal representation of a theory" ( Herman Adèr quoting Kenneth Bollen). All statistical hypothesis tests and all statistical estimators are derived via statistical models. More generally, statistical models are part of the foundation of statistical inference. Introduction Informally, a statistical model can be thought of as a statistical assumption (or set of statistical assumptions) with a certain property: that the assumption allows us to calculate the probability of any event. As an example, consider a pair of ordinary six-si ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Marzullo Example-3
Marzullo is a family name of Italian origin. Notable people with the name include: * Frank Marzullo, American meteorologist * Gianluca Marzullo, Italian-German footballer * Gigi Marzullo, Italian journalist * Keith Marzullo, American computer scientist See also * Marzullo's algorithm Marzullo's algorithm, invented by Keith Marzullo for his Ph.D. dissertation in 1984, is an agreement algorithm used to select sources for estimating accurate time from a number of noisy time sources. A refined version of it, renamed the "intersect ... {{surname, Marzullo Italian-language surnames ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Marzullo Example-1
Marzullo is a family name of Italian origin. Notable people with the name include: * Frank Marzullo, American meteorologist * Gianluca Marzullo, Italian-German footballer * Gigi Marzullo, Italian journalist * Keith Marzullo, American computer scientist See also * Marzullo's algorithm Marzullo's algorithm, invented by Keith Marzullo for his Ph.D. dissertation in 1984, is an agreement algorithm used to select sources for estimating accurate time from a number of noisy time sources. A refined version of it, renamed the "intersect ... {{surname, Marzullo Italian-language surnames ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Agreement Algorithm
Agreement may refer to: Agreements between people and organizations * Gentlemen's agreement, not enforceable by law * Trade agreement, between countries * Consensus, a decision-making process * Contract, enforceable in a court of law ** Meeting of the minds (a.k.a. mutual agreement), a common understanding in the formation of a contract * Pact, convention, or treaty between nations, sub-national entities, organizations, corporations Arts and media *''Agreement'', a 1978 book of poetry by Peter Seaton * ''Agreement'' (film), a 1980 Bollywood film Science and mathematics * Agreement (linguistics) or ''concord'', a change in the form of a word depending on grammatical features of another word * Consistency, logical agreement between two or more propositions * Reliability (statistics) in the sense of, for example, inter-rater agreement Other uses * Agreement (political party), a Polish political party * Operation Agreement, a British 1942 military operation during the Western Desert ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Consistent
In classical deductive logic, a consistent theory is one that does not lead to a logical contradiction. The lack of contradiction can be defined in either semantic or syntactic terms. The semantic definition states that a theory is consistent if it has a model, i.e., there exists an interpretation under which all formulas in the theory are true. This is the sense used in traditional Aristotelian logic, although in contemporary mathematical logic the term ''satisfiable'' is used instead. The syntactic definition states a theory T is consistent if there is no formula \varphi such that both \varphi and its negation \lnot\varphi are elements of the set of consequences of T. Let A be a set of closed sentences (informally "axioms") and \langle A\rangle the set of closed sentences provable from A under some (specified, possibly implicitly) formal deductive system. The set of axioms A is consistent when \varphi, \lnot \varphi \in \langle A \rangle for no formula \varphi. If there ex ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Confidence Interval
In frequentist statistics, a confidence interval (CI) is a range of estimates for an unknown parameter. A confidence interval is computed at a designated ''confidence level''; the 95% confidence level is most common, but other levels, such as 90% or 99%, are sometimes used. The confidence level represents the long-run proportion of corresponding CIs that contain the true value of the parameter. For example, out of all intervals computed at the 95% level, 95% of them should contain the parameter's true value. Factors affecting the width of the CI include the sample size, the variability in the sample, and the confidence level. All else being the same, a larger sample produces a narrower confidence interval, greater variability in the sample produces a wider confidence interval, and a higher confidence level produces a wider confidence interval. Definition Let be a random sample from a probability distribution with statistical parameter , which is a quantity to be estimate ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]