We explore the effect of dimensionality on the nearest neighbor problem. We show that under a broad set of conditions (much broader than independent and identically distributed dimensions), as dimensionality increases, the distance to the nearest data point approaches the distance to the farthest data point. To provide a practical perspective, we present empirical results on both real and synthetic data sets that demonstrate that this effect can occur for as few as 10-15 dimensions. These results should not be interpreted to mean that high-dimensional indexing is never meaningful; we illustrate this point by identifying some high-dimensional workloads for which this effect does not occur. However, our results do emphasize that the methodology used almost universally in the database literature to evaluate high-dimensional indexing techniques is flawed, and should be modified. In particular, most such techniques proposed in the literature are not evaluated versus simple linear scan, and are evaluated over workloads for which nearest neighbor is not meaningful. Often, even the reported experiments, when analyzed carefully, show that linear scan would outperform the techniques being proposed on the workloads studied in high (10-15) dimensionality!.

When is nearest neighbor meaningful

data types Sorting and searching parallel and distributed algorithms 3. [AR] Computer Architecture

/pdf/guide-to-the-software-engineering-body-of-knowledge-4x9ajlpq2m.pdf

Guide to the Software Engineering Body of Knowledge

We present the vision that for all fields of software engineering (SE), empirical research methods should enable the development of scientific knowledge about how useful different SE technologies are for different kinds of actors, performing different kinds of activities, on different kinds of systems. It is part of the vision that such scientific knowledge will guide the development of new SE technology and is a major input to important SE decisions in industry. Major challenges to the pursuit of this vision are: more SE research should be based on the use of empirical methods; the quality, including relevance, of the studies using such methods should be increased; there should be more and better synthesis of empirical evidence; and more theories should be built and tested. Means to meet these challenges include (1) increased competence regarding how to apply and combine alternative empirical methods, (2) tighter links between academia and industry, (3) the development of common research agendas with a focus on empirical methods, and (4) more resources for empirical research.

/pdf/the-future-of-empirical-methods-in-software-engineering-1bujrjy7uf.pdf

The Future of Empirical Methods in Software Engineering Research

Three decades of active research on the teaching of introductory programming has had limited effect on classroom practice. Although relevant research exists across several disciplines including education and cognitive science, disciplinary differences have made this material inaccessible to many computing educators. Furthermore, computer science instructors have not had access to a comprehensive survey of research in this area. This paper collects and classifies this literature, identifies important work and mediates it to computing educators and professional bodies.We identify research that gives well-supported advice to computing academics teaching introductory programming. Limitations and areas of incomplete coverage of existing research efforts are also identified. The analysis applies publication and research quality metrics developed by a previous ITiCSE working group [74].

A survey of literature on the teaching of introductory programming

A method and apparatus for the specification and automatic generation of user interfaces of information system (computer programs) is provided. The method is based in pattern language to specify requirements in an un-ambiguous mode and with precise semantics. The pattern language allows a user interface model to be composed using elements of the pattern language (computer objects in the object oriented programming style) which fully specify the desired user interface. The semantics of the objects in the user interface model have one and only one definition such that user interface model can be validated in a validation process. The validation process eliminates bugs in the final computer program code which is automatically produced from the user interface model. A model (metamodel), an editor tool (computer program) implementing the model for creating specifications of the user interface model, DTD specification, code generators, and other artifacts are depicted and described here for obtaining such user interfaces for different platforms (computers and operating systems) and different programming languages without manual coding of the computer code to implement the user interface. The software obtained is ready to run and it is able to communicate with a business server component using a standardized Application Programmatic Interface (API).

Method and apparatus for automatic generation of information system user interfaces

In recent years there has been increasing controversy surrounding the choice of a language for introducing programming to computer science majors The issue has been complicated by the increasing acceptance of the importance of non-procedural paradigms This paper compares the available vehicles for teaching programming to beginners These comparisons are based on the results of a survey conducted by the authors in early 1995 and on the published reports and opinions of other workers in this area

The first programming paradigm and language dilemma

Measurement of software reliability by life testing involves executing the software on large numbers of test cases and recording the results. The number of failures observed is used to bound the failure probability even if the number of failures observed is zero. Typical analyses assume that all failures that occur are observed, but, in practice, failures occur without being observed. In this paper, we examine the effect of imperfect error detection, i.e. the situation in which a failure of the software may not be observed. If a conventional analysis associated with life testing is used, the confidence in the bound on the failure probability is optimistic. Our results show that imperfect error detection does not necessarily limit the ability of life testing to bound the probability of failure to the very low values required in critical systems. However, we show that the confidence level associated with a bound on failure probability cannot necessarily be made as high as desired, unless very strong assumptions are made about the error detection mechanism. Such assumptions are unlikely to be met in practice, and so life testing is likely to be useful only for situations in which very high confidence levels are not required. >

The effect of imperfect error detection on reliability assessment via life testing

Research has shown that over 90% of all adults experience dental caries, and the early diagnosis of the carious lesion has become an important aspect of maintaining dental health. Advanced diagnostic and imaging devices can be used to identify tooth damage due to caries, compensating for the low sensitivity (high false negative) rate of visual and visual-tactile inspection by dentists. However, existing systems have such a high false positive rate that dentists often do not rely on the results, instead relying on traditional visual or visual-tactile inspection. Of the existing computer-aided diagnostic systems, few if any use digital image analysis for detection and diagnosis. By using digital images and a graphical user interface, our system will give both quantitative and qualitative feedback to dental practitioners, which will address the weaknesses of existing systems. This paper details our proposed system that makes use of commercial imaging equipment commonly owned by dental practices, including an intraoral camera, to process the digital images of teeth and quantitatively assess the presence and extent of caries on the surface of teeth. We demonstrate the feasibility of using advanced image processing techniques and a C4.5 decision tree classifier to accurately identify caries from digital images.

An image-processing enabled dental caries detection system

• The NSF Software Engineering Research Centers Program, which could have Centers oriented more towards software~ with appropriate industry participation as a success criterion. • The State of Califorrda's Micro program, which provides matching funds for industry-supported university research. • Establishing and coordinating counterpart initiatives for experimentation with advanced research concepts and capabilities in Federal missicm-oriented agencies (DoD, DoT, NASA, DoE, NIH, DoC, etc.) via HPCC-like mechanisms.

Empirical research in software engineering: a workshop

In this paper we report on a research project in which the user interface for a research nuclear reactor was specified using a combination of formal notations. The goal of the project was to evaluate the use of a combination of techniques and to assess their utility in specifying a user interface for a non-trivial safety-critical application. We conclude that the techniques worked well and scale up easily to the size of the application studied.

Susan S. Brilliant

Papers

The first programming paradigm and language dilemma

The effect of imperfect error detection on reliability assessment via life testing

An image-processing enabled dental caries detection system

Empirical research in software engineering: a workshop

Preliminary Evaluation of a Formal Approach to User Interface Specification