Fast Heavy Inner Product Identification Between Weights and Inputs in Neural Network Training

In this paper, we consider a heavy inner product identification problem, which generalizes the Light Bulb problem~(\cite{prr89}): Given two sets $A \subset \{-1,+1\}^d$ and $B \subset \{-1,+1\}^d$ with $|A|=|B| = n$, if there are exact $k$ pairs whose inner product passes a certain threshold, i.e., $\{(a_1, b_1), \cdots, (a_k, b_k)\} \subset A \times B$ such that $\forall i \in [k], \langle a_i,b_i \rangle \geq \rho \cdot d$, for a threshold $\rho \in (0,1)$, the goal is to identify those $k$ heavy inner products. We provide an algorithm that runs in $O(n^{2 \omega / 3+ o(1)})$ time to find the $k$ inner product pairs that surpass $\rho \cdot d$ threshold with high probability, where $\omega$ is the current matrix multiplication exponent. By solving this problem, our method speed up the training of neural networks with ReLU activation function.Comment: IEEE BigData 202

A framework for optimal decentralized service-choreography

Abstract We address the problem of optimizing mediator-based service composition where the services and the desired composition (goal

Privacy Aware Experiments without Cookies

Consider two brands that want to jointly test alternate web experiences for their customers with an A/B test. Such collaborative tests are today enabled using \textit{third-party cookies}, where each brand has information on the identity of visitors to another website. With the imminent elimination of third-party cookies, such A/B tests will become untenable. We propose a two-stage experimental design, where the two brands only need to agree on high-level aggregate parameters of the experiment to test the alternate experiences. Our design respects the privacy of customers. We propose an estimater of the Average Treatment Effect (ATE), show that it is unbiased and theoretically compute its variance. Our demonstration describes how a marketer for a brand can design such an experiment and analyze the results. On real and simulated data, we show that the approach provides valid estimate of the ATE with low variance and is robust to the proportion of visitors overlapping across the brands.Comment: Technical repor

I/O-Automata based formal approach to Web Services Choreography

Web Services are heterogeneously developed software components invoked over the network viz. the internet. Their main objective is to provide desired outputs in exchange of specified inputs. In the setting of service oriented architecture, Web services play a vital role by allowing computations to be carried out in a distributed fashion via communication between services over the network. This is commonly referred to as Web service composition. This amounts to investigating whether (and how) various services can be utilized in tandem to develop new services desired by a client. A wide range of problems needs to be addressed before service composition can be deployed in practice. These problems range from developing standard language representation for composite services to resolving semantic/vocabulary mismatch between services participating in a composition. In this dissertation we study the problem of synthesis of a mediator/choreographer in Web service composition for a given set of services and a goal. Services and goal are represented using i/o automata. The central theme of our technique relies on generating i/o automata representation of all possible choreographed behaviors of existing services (captured in form of universal service automaton, a concept introduced) and verifying that the goal can be simulated by the universal set of choreographed behaviors. Such a technique is subject to state-space explosion. In light of this, we have developed a tabled logic programming technique which generates and explores compositions in a goal-directed fashion to prove/disprove the existence of choreographer and to infer whether the desired functionality is realizable. We present a prototype implementation and show the practical applicability of our technique using composition problems with the corresponding computational savings in terms of number of states and transitions explored. However, such a centralized choreography mechanism can involve communication/computation overhead that can be reduced through its decentralized realization. With this as motivation, we next study the problem of synthesizing a decentralized choreography strategy that will have an optimum overhead for service composition by developing a set of site-specific choreographers working concurrently to implement a desired goal service. Each communication/computation is quantified by a cost. We develop algorithms that takes as input the existing services, the goal service, the costs and produces as an output a set of site-specific choreographers that optimally realize the goal service using the existing services. The optimization would be different in cases of the goal automaton without loops (workflow) or with loops (certain operations can be repeated any number of times). The contribution of this work lies in the automata-theoretic formal approach to the formulation and the systematic solution of the choreographer synthesis problem as well as formulation of the optimal decentralized choreographer synthesis problem and its solution. The contributions include a methodology for computing cost of automata (with or without cycles), given cost of its transitions, and a generalized solution of the optimized decentralization service composition problem.</p

Local and On-the-fly Choreography-based Web Service Composition ∗

We present a goal-directed, local and on-the-fly algorithm for verifying the existence of and synthesizing a choreographer for Web service composition. We use i/o-automata to represent the (existing/component) services, the desired functionality of the composition, and a choreographer to achieve the desired service by composing the existing ones [7]. As is the case with our prior work [7], choreographer existence and synthesis are typically performed by identifying all possible compositions realizable from the existing services and verifying whether one such composition conforms to the desired required functionality. Such a technique is subject to the state-space explosion as the computation of compositions is exponential to the number of components. In light of this, we have developed a tabledlogic programming technique which generates and explores compositions of the component services in a goal-directed fashion to prove or disprove the existence of choreographer and to infer whether the desired functionality is realizable. We present a prototype implementation and show the practical applicability of our goal-directed, local and on-the-fly technique using a variety of composition problems along with the corresponding computational savings in terms of the number of the states and transitions explored.

Automated choreographer synthesis for web services composition using i/o automata

We study the problem of synthesis of a choreogrpher in Web service composition for a given set of services and a goal. Services and goal are represented using i/o automata which can succinctly and precisely describe the interfaces of the services. Our technique considers existence and synthesis of two types of the choreographers: a simple choreographer capable of only relaying outputs from one service to input of another and a transducing choreographer which is capable of storing and reusing inputs/outputs from the services. The central theme of our technique relies on generating i/o automata representation of all possible choreographed behavior of existing services (captured in form of universal service automaton, a concept introduced in this paper) and verifying that the goal can be simulated by the universal set of choreographed behaviors.