Genetic programming as a means for programming computers by natural selection

Many seemingly different problems in machine learning, artificial intelligence, and symbolic processing can be viewed as requiring the discovery of a computer program that produces some desired output for particular inputs. When viewed in this way, the process of solving these problems becomes equivalent to searching a space of possible computer programs for a highly fit individual computer program. The recently developed genetic programming paradigm described herein provides a way to search the space of possible computer programs for a highly fit individual computer program to solve (or approximately solve) a surprising variety of different problems from different fields. In genetic programming, populations of computer programs are genetically bred using the Darwinian principle of survival of the fittest and using a genetic crossover (sexual recombination) operator appropriate for genetically mating computer programs. Genetic programming is illustrated via an example of machine learning of the Boolean 11-multiplexer function and symbolic regression of the econometric exchange equation from noisy empirical data.Hierarchical automatic function definition enables genetic programming to define potentially useful functions automatically and dynamically during a run, much as a human programmer writing a complex computer program creates subroutines (procedures, functions) to perform groups of steps which must be performed with different instantiations of the dummy variables (formal parameters) in more than one place in the main program. Hierarchical automatic function definition is illustrated via the machine learning of the Boolean 11-parity function.     

Simple approximations to the behrens—fisher distribution

Dayal and Dickey (1977) have published in this journal a rather efficient numerical integration procedure for the product of k Student t-densities, and point out the evaluation of Behrens-Fisher (BF) densities as an important special case. The present note adds to this three simple normal approximations to Behrens-Fisher tail probabilities, that will save computer time for someone using the Dayal-Dickey results, and even allow evaluation on a desk calculator for moderately large degrees of freedom.

A direct normal approximation (method U) will be too coarse unless both degrees of freedom are large. A combination of the Peizer-Pratt (1968) approximation to the t-distribution and the Patil (1965) t-approximation to the BF distribution turns out to be very accurate. For very small degrees of freedom it may still be refined by an adhoc correction presented below. Other approximations and expansions turn out to be less satisfactory than the present trio. It facilitates a quick evaluation of BF probabilities and quantiles on a small computer or even a pocket calculator.     

Statistical Computing Software Reviews

This section is similar in organization to a Book Review section in other journals; however, software of interest to statisticians is the subject of review here. Emphasis is on software for microcomputers. Programs that operate only in larger mainframe computers will seldom receive review. Normally, producers of programs make a copy of their product available to the Section Editor, who then selects one or more persons to test the product and prepare a review.

Producers of computer software who wish to have their product reviewed are invited to contact the Section Editor, Professor Kenneth Berk, Department of Mathematics, 313 Stevenson Hall, Illinois State University, Normal, IL 61761.

Findings and opinions expressed in every review are solely those of the author. They should not be construed as reflecting endorsement of the product, or opinions held, by the American Statistical Association, nor is any warranty implied about any product reviewed.

STAN, Version II.0. David M. Allen. Available from Statistical Consultants, Inc., 462 E. High Street, Lexington, KY 40508. $300. Reviewed by Peter A. Lachenbruch     

Equivalent inferences using transformations

Justice (1977) has presented a Leviiison-typc- solution for two dimensional Wiener filtering problem. Since the solution is based on the Szego polynomials, it is necessary to calculate the bivariate Szego polynomials to obtain it In this paper, an alternative solution of the problem is proposed, which is based on the block Cholesky decomposition of the inverse of a Hermi-tian block Toeplitz matrix. Since the block Choiesky decomposition can be accomplished through the Whittle algorithm, the new solution is easy to implement into a computer program.     

Using multivariate rank sum tests to evaluate effectiveness of computer applications in teaching business statistics

Arguments about using computer facilities in classroom teaching have received a lot of attention over time. Using the computer facilities will be helpful to demonstrate real-world applications, while poor data or inappropriate case studies might hinder the applications of the computer programs in classroom teaching. In this paper, we examine the impacts that using computer programs to teach business statistics have on students in the Krannert School of Management at Purdue University. The results show that students are attracted to the interactive computer programs designed for the business statistics course, and students are more motivated to attend classes when computer programs are applied in teaching. Furthermore, computer programs help students to understand confusing topics, and students feel that teaching them to use computer facilities really improves their own abilities to apply similar programs in analyzing real-world problems.     

大数据时代的统计教育

2014年11月,美国统计学会适应大数据时代的要求,发布了统计学本科专业指导性教学纲要。而在2013年,我国统计类本科专业刚刚进行了一次较大调整,目前的专业课程设置和教学内容改革还处于探索阶段。美国统计学会发布的这份指导性教学纲要对于推进我国统计类本科专业教育改革具有重要借鉴意义。本文首先概括性地介绍了美国统计学会发布的统计学本科专业指导性教学纲要的核心内容,包括统计专业本科生应该掌握的基本技能和应该修读的主要课程,然后分析了我国统计类本科专业教育存在的问题,并提出了在大数据时代改进我国统计类本科专业教育的几点建议。     

Testing hypotheses and estimating survival from capture histories with CR

Thanks to the progress of the methodology for survival analysis of capture-mark-recapture data, today biologists become able to test the individual or environmental factors that are likely to affect survival and, relatedly, they can estimate survival with a model that describes satisfactorily and efficiently the population and the experiment. Assessment of fit, adjustment and model selection are the main tasks in the process. Several computer programs exist with complementary abilities in those respects and, most often, one must use successively several of them in a single analysis. As there is no standardized presentation of the data, the transition from one program to another is not particularly easy. CR is a software package that intends to alleviate those difficulties by putting together some of the most popular programs and providing passageways between them. We explain how a typical analysis is carried out with CR and insist on the flexibility that can be achieved with SURGE, a program for designing and fitting survival models which is an integral part of CR. A real example is treated for illustration.     

Testing hypotheses and estimating survival from capture histories with CR

Thanks to the progress of the methodology for survival analysis of capture-mark-recapture data, today biologists become able to test the individual or environmental factors that are likely to affect survival and, relatedly, they can estimate survival with a model that describes satisfactorily and efficiently the population and the experiment. Assessment of fit, adjustment and model selection are the main tasks in the process. Several computer programs exist with complementary abilities in those respects and, most often, one must use successively several of them in a single analysis. As there is no standardized presentation of the data, the transition from one program to another is not particularly easy. CR is a software package that intends to alleviate those difficulties by putting together some of the most popular programs and providing passageways between them. We explain how a typical analysis is carried out with CR and insist on the flexibility that can be achieved with SURGE, a program for designing and fitting survival models which is an integral part of CR. A real example is treated for illustration.     

The statistician and the computer

This paper reviews the impact of the computer on the analysis and interpretation of data. It suggests the need for professonal statisticians to recognize that almost all future analysis of data will be carried out by non-statisticians with the aid of statistical program packages. Therefore, the emphasis of statistical training for scientists, engineers, administrators and decision-makers should be on the design of data collection and the choice of appropriate methods of analysis. Both in the teaching of statistics and in the development of computer programs for statistical analysis there are important and urgent tasks to be addressed by professional statisticians.     

Statistical Computing Software Reviews

This department includes the two sections New Developments in Statistical Computing and Statistical Computing Software Reviews; suitable contents for each of these sections is described under the respective section heading. Articles submitted for the department, outside the two sections, should not be highly technical and should be relevant to the teaching or practice of statistical computing.

This section is similar in organization to a Book Review section in other journals; however, software of interest to statisticians is the subject of review here. Emphasis is on software for microcomputers. Programs that operate only in larger mainframe computers will seldom receive review. Normally, producers of programs make a copy of their product available to the Section Editor, who then selects one or more persons to test the product and prepare a review.

Producers of computer software who wish to have their product reviewed are invited to contact the Section Editor, Professor Kenneth Berk, Department of Mathematics, 313 Stevenson Hall, Illinois State University, Normal, IL 61761.

Findings and opinions expressed in every review are solely those of the author. They should not be construed as reflecting endorsement of the product, or opinions held, by the American Statistical Association, nor is any warranty implied about any product reviewed.

SYSTAT Leland Wilkinson. Available from Systat, Inc., 603 Main St., Evanston, IL 60202. $495 (multiple copy and site fees available). Reviewed by Mark I. Scherwish

AIDA, Version 9/82 David A. Lingwood, Available from Action-Research Northwest, 11442 Marine View Drive, S.W., Seattle, WA 98146. $235. Reviewed by Walter Liggett

MSUSTAT, MS/PC-DOS and CP/M-80 Version 2.20 Richard E. Lund. Available from Research and Development, Inc., Montana State University, Bozeman, MT 59717–0002. $187.50 (university and multiple-copy discounts available). Reviewed by Mervyn G. Marasinghe     

Preparing Statisticians for Careers in Industry: Report of the ASA Section on Statistical Education Committee on Training of Statisticians for Industry

This report provides guidelines for universities to consider in developing programs for training statisticians who will work in industry. Useful information for students who are considering industrial employment is also included. The recommended programs focus on real problems and the statistical theory and methodology that are useful in their solution. Technical competence is only one of many factors that industry considers when hiring and promoting statisticians. When a statistician leaves school, his or her skills and experiences should include statistical knowledge, practical problem solving, consulting practice, and the ability to communicate orally and in writing with nonstatisticians. There are many details that must be worked out (e.g., content of specific courses and organization of consulting internship programs), and it is hoped that the statistical societies and universities will form committees, hold conferences, and develop programs to address these issues further. Many of our recommendations apply more broadly to the training of all types of practicing statisticians.     

A numerical nonmetric approach for analyzing time series data

A numerical nonmetric approach to data analysis of periodic series with polytone trend is suggested. Estimation is made of thesmallest number of tone (monotone segments) possible for the trend. The seasonal component is estimated without need for first removing the (estimated) polytone trend. A computer program has been developed which enables analysis of arbitrary series, either by a prespecified length of period or by estimating the period length if not known in advance. Robustness of the proposed approach enables analysis of very short series, series with missing values, and other series with limitations that cannot be easily handled otherwise. In a separate appendix some empirical results obtained by this approach are compared with those from the X-ll program; this appendix will be sent upon request.     

CONSER Editing Guide

Abstract

The 2011 American Library Association conference took place June 23–28 at the Morial Convention Center in New Orleans, Louisiana. This report summarizes several programs and forums including the Association for Library Collections and Technical Services (ALCTS) Continuing Resources Section, Electronic Resources Interest Group program; Holdings Forum: Universal and Repurposed Holdings Information: Emerging Initiatives and Projects; the RDA Update Forum; and the Continuing Resources Cataloging Committee Update Forum.     

An Eight-Step Guide to Creating and Sustaining a Mentoring Program

Mentoring is an extremely valuable activity for both individuals and organizations. Mentoring within organizations can develop and integrate employees into their corporate culture. Mentoring outside the mentees’ work groups or through professional development organizations can give broader perspective and support, especially in times of transition. But mentoring programs require tremendous effort to start, organize, and maintain. Few last more than two years. This article provides a structured approach to starting and sustaining a successful program. The steps include understanding an organization’s particular needs, learning from small pilot programs, following up with mentoring pairs during a committed formal mentoring period, and evaluating results from each program’s cycle to learn and grow the program. Supplementary materials for this article are available online.     

Comparison of One-Sided Tolerance Limits in Unbalanced One-Way Random Models

Cox's discrete logistic model was extended to the study of the life table by Thompson (1977) to handle grouped survival data. Inferences about the effect of grouping are studies byMonte Carlo methods. The results show that the effect of grouping is not substantial. This approach is applied to the grouped data on liver cancer. The computer program developed for grouped censored data with continuous and indicator covariates is of practical importance and is available fromThe Ohio State University     

Evaluation of program success for programs with multiple trials in binary outcomes

A late‐stage clinical development program typically contains multiple trials. Conventionally, the program's success or failure may not be known until the completion of all trials. Nowadays, interim analyses are often used to allow evaluation for early success and/or futility for each individual study by calculating conditional power, predictive power and other indexes. It presents a good opportunity for us to estimate the probability of program success (POPS) for the entire clinical development earlier. The sponsor may abandon the program early if the estimated POPS is very low and therefore permit resource savings and reallocation to other products. We provide a method to calculate probability of success (POS) at an individual study level and also POPS for clinical programs with multiple trials in binary outcomes. Methods for calculating variation and confidence measures of POS and POPS and timing for interim analysis will be discussed and evaluated through simulations. We also illustrate our approaches on historical data retrospectively from a completed clinical program for depression. Copyright © 2015 John Wiley & Sons, Ltd.     

Evaluation of vectorization/parallelization techniques: application to nonparametric curve estimation

The simulation of statistical models in a computer is a fundamental aspect of research in the field of nonparametric curve estimation. Methods such as the FFT (Fast Fourier Transform) or WARP (Weighted Average of Rounded Points) have been developed and analysed for computer implementation of the different techniques in this realm, with the aim of reducing the computation time as much as possible. In this work we analyse two techniques with this objective. These are the vectorization of the source code in which the different algorithms are implemented, and their distributed execution. It can be observed that the vectorization of the programs can improve the results obtained with techniques such as the FFT or WARP, or, in some cases, can prevent the use of these.