We describe a type system that identifies potential type errors in dynamically typed languages like Python. The system uses a flow-sensitive static analysis on bytecodes to compute, for every variable and program point, overapproximations of the variable’s present and future use types. If the future use types are not subsumed by the present types, the further program execution may raise a type ...

We present a novel statistical model reduction method which can significantly boost the speed of stochastic simulation of a population continuous-time Markov chain (PCTMC) model. This is achieved by identifying and removing agent types and transitions from the simulation which have only minor impact on the evolution of population dynamics of target agent types specified by the modeller. The err...

Data error is an obstacle to effective application, integration, and sharing of data. Error reduction, although desirable, is not always necessary or feasible. Error measurement is a natural alternative. In this paper, we outline an error propagation calculus which models the propagation of an error representation through queries. A closed set of three error types is defined: attribute value in...

Depending on the change in magnitude of analytical error occuring with change in concentration of analyte, two limiting types of error properties can be defined: additive and multiplicative. We investigated whether one of these two error types also characterizes the overall error of methods involving multiple procedural steps, or whether mixed error properties result in these cases. Using "open...

The specification of abstract data types requires the possibility to treat exceptions and errors. We present an approach allowing all forms of error handling: error introduction, error propagation and error recovery. The algebraic semantics of our method and a new correctness criterion are given. We also introduce an operational semanti es of a subdass of our specifications which coincides with...

The specification of abstract data types requires the possibility to treat exceptions and errors. We present an approach allowing all forms of error handling : error introduction, error propagation and error recovery. The algebraic semantics Of our method and a new correctness criterion is given. We also introduce an operational semantics of a subclass of our specifications which coincides with...

The error patterns of a wireless digital communication channel can be described by looking at consecutively correct or erroneous bits (runs and bursts) and at the distribution function of these run and burst lengths. A number of stochastic models exist that can be used to describe these distributions for wireless channels, e.g., the Gilbert-Elliot model. When attempting to apply these models to...

The transmission errors in H.264 may propagate in the temporal direction. Errors in intra-coded picture (I-frame) will propagate into the associated P-B frame if they are in the same Group Of Picture (GOP). Therefore it is important to detect errors in the I-frame rather than in the P-B frame. This paper proposes and demonstrates an effective technique of Error-Resilient Coding based on bit-err...

There is compelling evidence that typical decision-makers, including individual investors and even professional money managers, care about the difference between their portfolio returns and a reference point, or benchmark return. In the context of financial markets, likely benchmarks against which investors compare their own returns include easy-to-focus-on numbers such as one’s own past payoff...

the output error of the globoidal cam mechanism can be considered as a relevant indicator ofmechanism performance, because it determines kinematic and dynamical behavior of mechanicaltransmission. based on the differential geometry and the rigid body transformations, themathematical model of surface geometry of the globoidal cam is established. then we present theanalytical expression of the ou...