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## Perspesctivas da complexidade aplicadas à gestão de empresas.; Perspectives of complexity applied to management.

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Tese de Doutorado
Formato: application/pdf

Publicado em 28/03/2008
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O presente trabalho explora como duas abordagens gerais da complexidade - ciências da complexidade e pensamento complexo - estão influenciando e podem vir a influenciar a gestão de sistemas organizacionais produtivos. Constata-se um aumento de publicações que relacionam a Complexidade à Gestão. Por meio de análise de conteúdo de trabalhos acadêmicos internacionais e nacionais identifica-se uma diminuição na ênfase inicial sobre teoria do caos e fractais e uma tendência recente na exploração da dinâmica de redes, ao mesmo tempo em que modelos baseados em agentes são cada vez mais explorados (associados à idéia de sistemas adaptativos complexos - SAC). Na produção nacional nota-se também a presença de idéias de cunho mais filosófico relacionadas à complexidade, notoriamente as do pensamento complexo do francês Edgar Morin. Com base na história do pensamento científico são identificados fundamentos do paradigma mecanicista dominante e fatores que estão contribuindo para transição de fase desse paradigma, relacionados ao aumento de complexidade na ciência e ao surgimento das ciências da complexidade. Estas ciências são caracterizadas como um processo evolutivo da Teoria Geral de Sistemas e possuem uma diversidade de contribuições em evolução...

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## Utilização das horas de enfermagem em salas de operações, segundo a complexidade do paciente e do procedimento anestésico-cirúrgico; The utilization of nursing hours in operating rooms, according to the patient's complexity and the surgical anesthetic procedure

Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP

Tipo: Tese de Doutorado
Formato: application/pdf

Publicado em 04/12/2002
Português

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#Complexidade do paciente/procedimento anestésico-cirúrgico#Horas de enfermagem#Nursing hours#Operating room#Patient complexity/surgical anesthetic procedure#Salas de operações

Esta pesquisa é um estudo de caso, com natureza exploratória, descritiva e comparativa de campo, transversal e com abordagem quantitativa. Tem como objetivo classificar as cirurgias em categorias, segundo a necessidade de horas de enfermagem em salas de operações, subsidiando o dimensionamento de pessoal de enfermagem em centro cirúrgico. Foi realizada em um Hospital geral, de grande porte, da rede privada da cidade de São Paulo. A amostra foi constituída de 140 pacientes, divididos em 14 grupos, sendo 10 pacientes em cada grupo. Para a formação dos grupos foi considerado a condição física do paciente, segundo Americam Society of Anestesiologists (ASA), o porte anestésico segundo a Associação Médica Brasileira (AMB), o tipo de procedimento anestésico-cirúrgico, invasivo ou minimamente invasivo (MI) e cirurgias eletivas. Quanto à condição física do paciente, os grupos foram formados com ASA1, ASA2 e ASA3; a ASA4 foi excluída por não apresentar casos, ASA 5 e 6 foram excluídos por serem cirurgias de urgência ou emergência. Quanto ao porte anestésico, as cirurgias foram classificadas em pequeno porte, médio porte, grande porte e porte especial. Desta forma os grupos ficaram simbolizados como: 1P, 1M, 1G, 1E...

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## Análise formal da complexidade de algoritmos genéticos; Formal analysis of genetic algorithms complexity

Fonte: Universidade Federal do Rio Grande do Sul
Publicador: Universidade Federal do Rio Grande do Sul

Tipo: Dissertação
Formato: application/pdf

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O objetivo do trabalho é estudar a viabilidade de tratar problemas de otimização, considerados intratáveis, através de Algoritmos Genéticos, desenvolvendo critérios para a avaliação qualitativa de um Algoritmo Genético. Dentro deste tema, abordam-se estudos sobre complexidade, classes de problemas, análise e desenvolvimento de algoritmos e Algoritmos Genéticos, este ultimo sendo objeto central do estudo. Como produto do estudo deste tema, é proposto um método de desenvolvimento de Algoritmos Genéticos, utilizando todo o estudo formal de tipos de problemas, desenvolvimento de algoritmos aproximativos e análise da complexidade. O fato de um problema ser teoricamente resolvível por um computador não é suficiente para o problema ser na prática resolvível. Um problema é denominado tratável se no pior caso possui um algoritmo razoavelmente eficiente. E um algoritmo é dito razoavelmente eficiente quando existe um polinômio p tal que para qualquer entrada de tamanho n o algoritmo termina com no máximo p(n) passos [SZW 84]. Já que um polinômio pode ser de ordem bem alta, então um algoritmo de complexidade polinomial pode ser muito ineficiente. Genéticos é que se pode encontrar soluções aproximadas de problemas de grande complexidade computacional mediante um processo de evolução simulada[LAG 96]. Como produto do estudo deste tema...

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## The effects of habitat complexity and hydraulic conditions on the establishment of benthic stream macroalgae

Fonte: Wiley-Blackwell
Publicador: Wiley-Blackwell

Tipo: Artigo de Revista Científica
Formato: 1687-1694

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 07/52608-1; Processo FAPESP: 12/21196-8; Processo FAPESP: 10/17563-0; 1. Habitat complexity is thought to play an important role in various ecological communities, but its role under variable natural conditions is not well understood, particularly in lotic habitats where the complexity of the substratum influences the diversity and abundance of the benthic community.2. We investigated the effects of the habitat complexity of the substratum, as represented by fractal structure, on the establishment of stream macroalgae. We also analysed the influence of hydraulic conditions associated with variations in the fractal dimension of the substratum. We hypothesised that habitats with higher surface complexity would have higher macroalgal abundance and that hydraulic conditions would affect macroalgal establishment differently on surfaces of differing complexity.3. We designed a field experiment to elucidate the role of habitat complexity (represented by the fractal dimension and density of roughness elements) and consequent hydraulic conditions (assessed by the Reynolds number and drag forces) on algal growth. Sterile artificial substrata with five levels of complexity were placed in four unshaded streams. After 60 days of complete submergence...

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## Advice for Semifeasible Sets and the Complexity-Theoretic Cost(lessness) of Algebraic Properties

Fonte: University of Rochester. Computer Science Department.
Publicador: University of Rochester. Computer Science Department.

Tipo: Relatório

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#algebraic properties#P/linear#NP/linear#advice complexity#selector functions#semifeasible computation#P-selectivity#associativity#commutativity#linear advice

This paper provides a tutorial overview of the advice complexity of the semifeasible sets---informally put, the class of sets having a polynomial-time algorithm that, given as input any two strings of which at least one belongs to the set, will choose one that does belong to the set. No previous familiarity with either the semifeasible sets or advice complexity will assumed, and when we include proofs we will try to make the material as accessible as possible via providing intuitive, informal presentations. Karp and Lipton (1980) introduced advice complexity about a quarter of a century ago. Advice complexity asks, for a given power of interpreter, how many bits of ``help' suffice to accept a given set. Thus, this is a notion that contains aspects both of informational complexity and of computational complexity. We will see that for some powers of interpreter the (worst-case) complexity of the semifeasible sets is known right down to the bit (and beyond), but that for the most central power of interpreter---deterministic polynomial time---the complexity is currently known only to be at least linear and at most quadratic. While overviewing the advice complexity of the semifeasible sets, we will stress also the issue of whether the functions at the core of semifeasibility---so-called selector functions---can without cost be chosen to possess such algebraic properties as commutativity and associativity. We will see that this is relevant...

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## Communication Complexity

Fonte: University of Rochester. Computer Science Department.
Publicador: University of Rochester. Computer Science Department.

Tipo: Relatório

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Ph.D. Thesis, Computer Science Dept., U. Rochester, Gary L. Peterson, thesis advisor; simultaneously published in the Technical Reprt series; A complete and formal model of computation for a network of two communicating processes is presented which uses an extension of the Turing Machine called a Communicating Turing Machine (CTM). The resources of number of symbols exchanged and maximum amount of local storage used between messages are identified and referred to as the communication time and communication space respectively. As a pair of processors, each with its own input, a fortiori accepts a set of pairs of strings, some consideration must be given to the mapping of problems to CTM inputs. A model parameter is this input mapping function. In addition to consideration of the usual partition mapping, we introduce a distribution mapping which bounds only the number of fragments into which an input is divided, and all partitions with this fragmentation are allowed. Complexity classes for each input mapping function are identified. A full, dense hierarchy is shown to exist in communication space and time from constant up to linear. For distribution input mappings, it is shown that the constant complexity classes are exactly the regular languages and that there is a gap between constant and log log n in the space hierarchy. For fair partition input mappings most of the structure of standard TM complexity obtains for Communication Complexity. An upper bound is given for the communication space complexity of Context Free languages and it is shown that the bound is met for bounded-fragmentation partitions. Example languages demonstrate that most complexity class relationships under fair partitions cannot be improved. An algorithm is presented that optimizes the communication time complexity of an existing communication protocol for a finite language. A new lower bound for communication complexity is presented which uses the number of equivalence classes of strings induced by the language and the input mapping function independently. It is shown that this lower bound is within a constant factor of the required minimum for communication time on fixed-cut partition input mappings.

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## Using Randomness to Characterize the Complexity of Computation

Fonte: University of Rochester. Computer Science Department.
Publicador: University of Rochester. Computer Science Department.

Tipo: Relatório

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extends Cornell Computer Science Dept. TR86-795; Kolmogorov complexity-the study of the randomness of strings-has developed into a fundamental tool in proving lower bounds in computation and in constructing oracles separating complexity classes. In this paper, we show that Kolmogorov complexity is a central tool in the understanding of deterministic and nondeterministic complexity classes and hierarchies; we show that many collapses of computational complexity classes can be completely characterized in terms of Kolmogorov complexity. We discuss P, NP, unique polynomial time, the polynomial hierarchy, and the exponential hierarchy. We show that, for many complexity classes C, C equals a smaller complexity class unless some language in C is accepted only by machines whose execution creates computational structures with a non-trivial degree of randomness. Our fundamental proof technique is a divide and conquer scheme on the tree of potential computational structures.

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## Economic complexity, regime transition and sectoral forces: the impact of trade unions on democratization in Zimbabwe, South Africa and Zambia

Fonte: University of Limerick
Publicador: University of Limerick

Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations

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peer-reviewed; This thesis interrogates uncertainty in transitional politics in South Africa, Zambia,
and Zimbabwe. It questions why some countries transition to democracy and some
stagnate or revert to authoritarianism. To address the dual nature of political
contingency and structural formations in transitional politics, it adopts a conceptual
framework based on economic complexity, to ascertain the relationship between
economic structures and the results of regime transition. This study engages with the
extensive literature linking economic development and democracy throughout the
world, to see if it can be applied to the recent and on-going transitional events across
Africa. It identified trade union confederations as economically important actors
whose political contingency was directly affected by the sectoral composition of
each country’s economy. In other world regions, trade unions have been of import
in determining transitional outcomes, and this thesis interrogated whether the same
was true in three African countries.
The concept of economic complexity was developed to offer a conceptual
framework through which to understand transitional politics. It was argued that the
more complex the economy, the more likely democracy was to emerge following
transition because there would be more factors in play in the political-economic
arena that could erode a regime’s relative power and thus bestow power onto other
actors who could utilize it for regime change. In terms of indicators...

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## Information Complexity Density and Simulation of Protocols

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Português

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A simulation of an interactive protocol entails the use of interactive
communication to produce the output of the protocol to within a fixed
statistical distance $\epsilon$. Recent works have proposed that the
information complexity of the protocol plays a central role in characterizing
the minimum number of bits that the parties must exchange for a successful
simulation, namely the distributional communication complexity of simulating
the protocol. Several simulation protocols have been proposed with
communication complexity depending on the information complexity of the
simulated protocol. However, in the absence of any general lower bounds for
distributional communication complexity, the conjectured central role of
information complexity is far from settled. We fill this gap and show that the
distributional communication complexity of $\epsilon$-simulating a protocol is
bounded below by the $\epsilon$-tail $\lambda_\epsilon$ of the information
complexity density, a random variable with information complexity as its
expected value. For protocols with bounded number of rounds, we give a
simulation protocol that yields a matching upper bound. Thus, it is not
information complexity but $\lambda_\epsilon$ that governs the distributional
communication complexity.
As applications of our bounds...

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## Communication complexity of promise problems and their applications to finite automata

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 30/09/2013
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#Computer Science - Computational Complexity#Computer Science - Formal Languages and Automata Theory#Quantum Physics

Equality and disjointness are two of the most studied problems in
communication complexity. They have been studied for both classical and also
quantum communication and for various models and modes of communication.
Buhrman et al. [Buh98] proved that the exact quantum communication complexity
for a promise version of the equality problem is ${\bf O}(\log {n})$ while the
classical deterministic communication complexity is $n+1$ for two-way
communication, which was the first impressively large (exponential) gap between
quantum and classical (deterministic and probabilistic) communication
complexity. If an error is tolerated, both quantum and probabilistic
communication complexities for equality are ${\bf O}(\log {n})$. However, even
if an error is tolerated, the gaps between quantum (probabilistic) and
deterministic complexity are not larger than quadratic for the disjointness
problem. It is therefore interesting to ask whether there are some promise
versions of the disjointness problem for which bigger gaps can be shown. We
give a positive answer to such a question. Namely, we prove that there exists
an exponential gap between quantum (even probabilistic) communication
complexity and classical deterministic communication complexity of some
specific versions of the disjointness problem.
Klauck [Kla00] proved...

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## Approximation for the Path Complexity of Binary Search Tree

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 18/04/2014
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The complexity of an algorithm is an important parameter to determine its
effi-ciency. They are of different types viz. Time complexity, Space
complexity, etc. However, none of them consider the execution path as a
complexity measure. Ashok et al, firstly proposed the notion of the Path
Complexity of a pro-gram/algorithm, which defined based on the number of
execution paths as a function of the input size. However, the notion of path
complexity of the pro-gram, cannot apply to the object-oriented environment.
Therefore, Anupam et al, has extended the notion of path complexity to the
class as follows. The notion of the state of the class is defined based on
structural representation (aka state) of the class. The class contains data
members and data operations. It considers only those data operations that
change the state of the class. The path complexity of the class is defined to
be the number of valid input sequences, each of them con-taining valid data
operations. Anupam et al, had applied this notion to the class Stack. However,
the stack is basic and simple data structures. Therefore, in this research we
have used a more complex class to understand the path complexity behavior in
the object oriented environment. Binary Search Tree (BST) is one of the well
known (and more complex too) data structure...

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## Query complexity in expectation

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 26/11/2014
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We study the query complexity of computing a function f:{0,1}^n-->R_+ in
expectation. This requires the algorithm on input x to output a nonnegative
random variable whose expectation equals f(x), using as few queries to the
input x as possible. We exactly characterize both the randomized and the
quantum query complexity by two polynomial degrees, the nonnegative literal
degree and the sum-of-squares degree, respectively. We observe that the quantum
complexity can be unboundedly smaller than the classical complexity for some
functions, but can be at most polynomially smaller for functions with range
{0,1}.
These query complexities relate to (and are motivated by) the extension
complexity of polytopes. The linear extension complexity of a polytope is
characterized by the randomized communication complexity of computing its slack
matrix in expectation, and the semidefinite (psd) extension complexity is
characterized by the analogous quantum model. Since query complexity can be
used to upper bound communication complexity of related functions, we can
derive some upper bounds on psd extension complexity by constructing efficient
quantum query algorithms. As an example we give an exponentially-close
entrywise approximation of the slack matrix of the perfect matching polytope
with psd-rank only 2^{n^{1/2+epsilon}}. Finally...

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## Partition Arguments in Multiparty Communication Complexity

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 30/09/2009
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Consider the "Number in Hand" multiparty communication complexity model,
where k players holding inputs x_1,...,x_k in {0,1}^n communicate to compute
the value f(x_1,...,x_k) of a function f known to all of them. The main lower
bound technique for the communication complexity of such problems is that of
partition arguments: partition the k players into two disjoint sets of players
and find a lower bound for the induced two-party communication complexity
problem.
In this paper, we study the power of partition arguments. Our two main
results are very different in nature: (i) For randomized communication
complexity, we show that partition arguments may yield bounds that are
exponentially far from the true communication complexity. Specifically, we
prove that there exists a 3-argument function f whose communication complexity
is Omega(n), while partition arguments can only yield an Omega(log n) lower
bound. The same holds for nondeterministic communication complexity. (ii) For
deterministic communication complexity, we prove that finding significant gaps
between the true communication complexity and the best lower bound that can be
obtained via partition arguments, would imply progress on a generalized version
of the "log-rank conjecture" in communication complexity.
We conclude with two results on the multiparty "fooling set technique"...

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## R\'enyi Information Complexity and an Information Theoretic Characterization of the Partition Bound

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 25/11/2015
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We introduce a new information-theoretic complexity measure $IC_\infty$ for
2-party functions which is a lower-bound on communication complexity, and has
the two leading lower-bounds on communication complexity as its natural
relaxations: (external) information complexity ($IC$) and logarithm of
partition complexity ($\text{prt}$) which have so far appeared conceptually
quite different from each other. $IC_\infty$ is an external information
complexity based on R\'enyi mutual information of order infinity. In the
definition of $IC_\infty$, relaxing the order of R\'enyi mutual information
from infinity to 1 yields $IC$, while $\log \text{prt}$ is obtained by
replacing protocol transcripts with what we term "pseudotranscripts," which
omits the interactive nature of a protocol, but only requires that the
probability of any transcript given the inputs $x$ and $y$ to the two parties,
factorizes into two terms which depend on $x$ and $y$ separately. Further
understanding $IC_\infty$ might have consequences for important direct-sum
problems in communication complexity, as it lies between communication
complexity and information complexity.
We also show that applying both the above relaxations simultaneously to
$IC_\infty$ gives a complexity measure that is lower-bounded by the (log of)
relaxed partition complexity...

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## On Arthur Merlin Games in Communication Complexity

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 03/01/2011
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We show several results related to interactive proof modes of communication
complexity. First we show lower bounds for the QMA-communication complexity of
the functions Inner Product and Disjointness. We describe a general method to
prove lower bounds for QMA-communication complexity, and show how one can
'transfer' hardness under an analogous measure in the query complexity model to
the communication model using Sherstov's pattern matrix method. Combining a
result by Vereshchagin and the pattern matrix method we find a communication
problem with AM-communication complexity $O(\log n)$, PP-communication
complexity $\Omega(n^{1/3})$, and QMA-communication complexity
$\Omega(n^{1/6})$. Hence in the world of communication complexity
noninteractive quantum proof systems are not able to efficiently simulate
co-nondeterminism or interaction. These results imply that the related
questions in Turing machine complexity theory cannot be resolved by
'algebrizing' techniques. Finally we show that in MA-protocols there is an
exponential gap between one-way protocols and two-way protocols (this refers to
the interaction between Alice and Bob). This is in contrast to
nondeterministic, AM-, and QMA-protocols, where one-way communication is
essentially optimal.; Comment: 19 pages

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## Separations in Query Complexity Based on Pointer Functions

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Português

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In 1986, Saks and Wigderson conjectured that the largest separation between
deterministic and zero-error randomized query complexity for a total boolean
function is given by the function $f$ on $n=2^k$ bits defined by a complete
binary tree of NAND gates of depth $k$, which achieves $R_0(f) =
O(D(f)^{0.7537\ldots})$. We show this is false by giving an example of a total
boolean function $f$ on $n$ bits whose deterministic query complexity is
$\Omega(n/\log(n))$ while its zero-error randomized query complexity is $\tilde
O(\sqrt{n})$. We further show that the quantum query complexity of the same
function is $\tilde O(n^{1/4})$, giving the first example of a total function
with a super-quadratic gap between its quantum and deterministic query
complexities.
We also construct a total boolean function $g$ on $n$ variables that has
zero-error randomized query complexity $\Omega(n/\log(n))$ and bounded-error
randomized query complexity $R(g) = \tilde O(\sqrt{n})$. This is the first
super-linear separation between these two complexity measures. The exact
quantum query complexity of the same function is $Q_E(g) = \tilde O(\sqrt{n})$.
These two functions show that the relations $D(f) = O(R_1(f)^2)$ and $R_0(f)
= \tilde O(R(f)^2)$ are optimal...

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## Sample Complexity Bounds on Differentially Private Learning via Communication Complexity

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Português

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#Computer Science - Data Structures and Algorithms#Computer Science - Computational Complexity#Computer Science - Learning

In this work we analyze the sample complexity of classification by
differentially private algorithms. Differential privacy is a strong and
well-studied notion of privacy introduced by Dwork et al. (2006) that ensures
that the output of an algorithm leaks little information about the data point
provided by any of the participating individuals. Sample complexity of private
PAC and agnostic learning was studied in a number of prior works starting with
(Kasiviswanathan et al., 2008) but a number of basic questions still remain
open, most notably whether learning with privacy requires more samples than
learning without privacy.
We show that the sample complexity of learning with (pure) differential
privacy can be arbitrarily higher than the sample complexity of learning
without the privacy constraint or the sample complexity of learning with
approximate differential privacy. Our second contribution and the main tool is
an equivalence between the sample complexity of (pure) differentially private
learning of a concept class $C$ (or $SCDP(C)$) and the randomized one-way
communication complexity of the evaluation problem for concepts from $C$. Using
this equivalence we prove the following bounds:
1. $SCDP(C) = \Omega(LDim(C))$, where $LDim(C)$ is the Littlestone's (1987)
dimension characterizing the number of mistakes in the online-mistake-bound
learning model. Known bounds on $LDim(C)$ then imply that $SCDP(C)$ can be much
higher than the VC-dimension of $C$.
2. For any $t$...

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## Nearly optimal separations between communication (or query) complexity and partitions

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 03/12/2015
Português

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We show a nearly quadratic separation between deterministic communication
complexity and the logarithm of the partition number, which is essentially
optimal. This improves upon a recent power 1.5 separation of G\"o\"os, Pitassi,
and Watson (FOCS 2015). In query complexity, we establish a nearly quadratic
separation between deterministic (and even randomized) query complexity and
subcube partition complexity, which is also essentially optimal. We also
establish a nearly power 1.5 separation between quantum query complexity and
subcube partition complexity, the first superlinear separation between the two
measures. Lastly, we show a quadratic separation between quantum query
complexity and one-sided subcube partition complexity.
Our query complexity separations use the recent cheat sheet framework of
Aaronson, Ben-David, and the author. Our query functions are built up in stages
by alternating function composition with the cheat sheet construction. The
communication complexity separation follows from lifting the query separation
to communication complexity.; Comment: 13 pages

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## Lower Bounds on the Oracle Complexity of Nonsmooth Convex Optimization via Information Theory

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 19/07/2014
Português

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#Mathematics - Optimization and Control#Computer Science - Computational Complexity#Computer Science - Information Theory

We present an information-theoretic approach to lower bound the oracle
complexity of nonsmooth black box convex optimization, unifying previous lower
bounding techniques by identifying a combinatorial problem, namely string
guessing, as a single source of hardness. As a measure of complexity we use
distributional oracle complexity, which subsumes randomized oracle complexity
as well as worst-case oracle complexity. We obtain strong lower bounds on
distributional oracle complexity for the box $[-1,1]^n$, as well as for the
$L^p$-ball for $p \geq 1$ (for both low-scale and large-scale regimes),
matching worst-case lower bounds, and hence we close the gap between
distributional complexity, and in particular, randomized complexity, and
worst-case complexity. Furthermore, the bounds remain essentially the same for
high-probability and bounded-error oracle complexity, and even for combination
of the two, i.e., bounded-error high-probability oracle complexity. This
considerably extends the applicability of known bounds.

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## Economic complexity, regime transition and sectoral forces: the impact of trade unions on democratization in Zimbabwe, South Africa and Zambia

Fonte: University of Limerick
Publicador: University of Limerick

Tipo: info:eu-repo/semantics/doctoralThesis; all_ul_research; ul_published_reviewed; ul_theses_dissertations

Português

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36.44%

peer-reviewed; This thesis interrogates uncertainty in transitional politics in South Africa, Zambia,
and Zimbabwe. It questions why some countries transition to democracy and some
stagnate or revert to authoritarianism. To address the dual nature of political
contingency and structural formations in transitional politics, it adopts a conceptual
framework based on economic complexity, to ascertain the relationship between
economic structures and the results of regime transition. This study engages with the
extensive literature linking economic development and democracy throughout the
world, to see if it can be applied to the recent and on-going transitional events across
Africa. It identified trade union confederations as economically important actors
whose political contingency was directly affected by the sectoral composition of
each country’s economy. In other world regions, trade unions have been of import
in determining transitional outcomes, and this thesis interrogated whether the same
was true in three African countries.
The concept of economic complexity was developed to offer a conceptual
framework through which to understand transitional politics. It was argued that the
more complex the economy, the more likely democracy was to emerge following
transition because there would be more factors in play in the political-economic
arena that could erode a regime’s relative power and thus bestow power onto other
actors who could utilize it for regime change. In terms of indicators...

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