bluuebunny/crossref_metadata_2025_split huggingface dataset:
Het gebruik van computers bij econometrisch onderzoek*
Authors: Cramer J. S. 
Published: April 2008

SummaryComputers permit data‐processing on a large scale, and more important, admit of the automatic control of the computing process on the basis of intermediate results. Econometric research stands to benefit largely from the first facility as there is a large volume of micro‐economic data that has hitherto remained unused. It is doubtful, however, whether econometrics can as yet make full use of the second possibility; much of it is of an experimental character and demands frequent decisions based on the judgement of the research worker. At present the main need is for research workers to exploit the computational facilities rather than for computing capacity in itself.
Voorraadbeheer en computer*
Authors: van Ham Ir. C. J. G. J. 
Published: April 2008

SummaryBoth in the design of a stock control system and in the routine performance of this system, a computer can be used. A case study concerning stock control of fasteners destined for assembling and maintenance departments will illustrate some possibilities and limitations in the use of a computer. Particular attention will be paid to the exponential smoothing method which has for object the extrapolation of time series, such as sequences of demand figures.
Een analyse van grondwaterstanden die beïnvloed worden door de getijdebeweging*
Authors: Stol Ir. Ph. Th. 
Published: April 2008

SummaryIn hydrology and water management research knowledge of the cause of changes in groundwater levels often is of great importance. Changes of ground‐waterlevel can be caused by precipitation and evaporation, by positive ‐ or negative seepage, by polder‐discharge and local discharges for industrial needs: along tidal‐rivers also by the influence of the tides. The effect of the tide (R) and of local discharges (P) together, give several types of groundwater level‐curves (Jig. 2). The propagation of the tide takes place with a shift in phase (tt in (I)) and a damping of the amplitude (fig. 6). To determine in an empirical way the rate with which the phase shifts, in connection with the distance (x)from the banks of the river, a simple regression model (2) is recalculated several times, shifting mutually the series of data before each calculation. This work can easily be done by means of a computer, loading in sequence the data of the test‐wells (W) located in the region under discussion (fig. I). That shift which results in the highest multiple correlation‐coefficient is used to determine the difference in phase with reference to the tide present in the river (table 1, giving the effect of increasing phase shift (tB) on the correlation coefficients, with in the columns: phase shift in hours; mult. corr. coeff.; time in degrees; corr. with river level). The results, for instance the numerical values of the correlation between each test well and the river, critical values of deviations from the model, the regression coeff. (b2) for local effects, are represented in maps (Jig. 3, 4, 5), and may serve to determine the magnitude of soil‐physical constants.
Simulatie van Leerprocessen: geprogrammeerde experimenten; een experimenteel programma*
Authors: Dirkzwoger A. 
Published: April 2008

SummaryHuman verbal learning is considered as an interaction between two information‐processing systems (e.g. the teacher and his pupil) by which one or both are modified. We discussed the possibilities of using a computer program to define one of these systems, which is then simulated by the computer with a human subject as the other system.The problems in writing such a program stem from the lack of an adequate and precise psychological theory of human learning and from the complexity and uniqueness of the verbal repertoire with which a subject enters the situation.A program is presented which establishes a behavior pattern in the subject by using only stimuli which are meaningless to him at the beginning of the interaction; he might e.g. label any stimulus or any response “right” or “wrong” if he felt like doing so. The responses were given by means of 16 on‐off switches, the stimuli consisted of light patterns in 27 lamps. The patterns were contingent on the foregoing stimulus response sequence and they were generated by the computer. The meaning of the program (unknown to the subject) was to teach operations of binary arithmetic. The only instruction given was that the program simulated a first contact by radio with inhabitants of another planet.The introspection protocols revealed that the subjects could remain ignorant of the real purpose of the program and attach quite a different meaning to their interaction with the computer, even in cases where the intended behavior‐pattern was successfully taught.In conclusion the method of studying human behavior by modifying the program governing the computer which interacts with the subject is discussed in relation to a more static and statistical approach.
The geometry of log‐normal and related distributions and an application to tracer‐dilution curves
Authors: Wise M. E. 
Published: April 2008

SummaryMost of a typical log‐normal curve lies very close to two straight lines, namely the tangents at its points of inflection. This holds good for nearly all the rising part of the curve and for most of the top half beyond the maximum.When loge (t – to) is normally distributed with standard deviation s̀, whether the whole curve can be observed or not, s̀, to, the mean, the mode and the area under the whole curve can be derived from the triangle formed by these two tangents and the base line. The triangle also provides a simple test of goodness‐of‐fit. The corresponding inflection triangles of two other skew distributions are investigated in outline namely a chi2 (or gamma) distribution and one arising in Brownian movement or random walk in one dimension with drift. These are compared with the log‐normal one. The normal distribution and its inflection triangle are given as a limiting case of the log‐normal one and it is shown that the curve on the cover of Statistica Neerlandica cannot be a normal one.The application is to the extrapolation problem in heart dye‐dilution curves, which record the distribution of passage times of an indicator through the lungs and heart. The usual semi‐log extrapolation for determining the area under the complete curve is discussed critically; it is shown how the inflection triangle provides a simpler procedure that is probably more accurate. The general formulae, an outline of the application and numerical tables for 0 < s̀ 0.8 are given in the main text; the mathematical derivations of all the basic formulae are in an appendix (sections 11 to 16).The information needed for practical applications without studying the theory is contained in sections 3 to 6 and the associated tables and figures.
On Some Nonparametric Tests of Dispersion
Authors: Peritz Eric 
Published: April 2008

SummaryLet X and Y be random variables with distribution functions F and G and medians ζand η, respectively. X will be said to be more dispersed about the median than Y if F(x+ζ) – F(–x+ζ) G (x+η) – G (–x+η)for all x > O, with sharp inequality holding for some positive x. Asymptotically nonparametric tests for the hypothesis that F (x+ζ) = G (x+η) against alternatives of the above type (for ζ and η unknown), provided F(x+ζ) (but not necessarily G (x+η)) is symmetric and Fand G have bounded densities, are constructed from a subclass Of SUKHATME'S modified generalized U ‐ statistics [12]. One simple test of this subclass turns out to be the MANN‐WHITNEY test as performed on the |Xi–ζ| and | Yj–η| where ζ and η are the corresponding sample medians. Consistency and PITMAN efficiencies of some of the tests proposed are discussed under two families of alternatives in which the Y's differ from the X's through departure from symmetry as well as by being more (less) dispersed: a model of “heterogeneous response” and the wellknown gross error model. The usual scale alternatives are also studied and the relationship of our tests to those previously given in the literature is pointed out.
The distribution of the brightness of stars. A Poisson‐process with “time”‐dependent parameter
Authors: Prins H. J. 
Published: April 2008

SamenvattingBij de optische waarneming van sterren uit een satelliet is het belangrijk voor het richtmechanisme te weten wat de verdeling van de helderheid van de helderste ster en van het verschil in helderheid van de helderste en op een na helderste is op de verzameling van alle mogelijke te kiezen gezichtsveldjes van de kijker.Het model is een Poisson‐proces met “tijds” afhankelijke parameter. Een monotone transformatie voert dit proces over in een tijdsonafhankelijk proces, waarna toepassing van bekende eigenschappen tot de oplossing leidt.Een dusdanige transformatie lijkt ook voor andere tijdsafhankelijke processen een nuttig middel om een oplossing te verkrijgen.
Transformatie van niet‐normale verdelingen
Authors: Flapper P. 
Published: April 2008

SummaryIn statistical analysis and operational research many techniques are being applied, which are based upon the fact that the phenomenon under consideration has a distribution, which is approximately normal. This distribution‐type has got a number of very nice properties and a constant pattern, so that “normal” phenomenona can be predicted. In case of non‐normal, but deviated or skew distributions, analysis and forecasting become much more complicated. In this article a method has been described in which some non‐normal variables can be transformed into normal ones, so that techniques based on normal distributions may be used.
Oneindige verwachting en de wet van de grote aantallen
Authors: MIJNHEER J. L. 
Published: April 2008

SamenvattingDe beide wetten van de grote aantallen (de zwakke en de sterke) vormen een centraal punt van de kansrekening. In het onderstaande wordt op eenvoudige wijze aangetoond, dat zij ook gelden voor steekproeven uit verdelingen met oneindige verwachting. Een minder eenvoudig bewijs is te vinden in M. LOÈVE, Probability Theory, Princeton 1963.Dehiergebruikte bewijsmethode werddeschrijver aanbevolen door dr. J. FABIUS.
Bepaling van de personeelssterkte op kostenbasis*
Authors: Knaap J. v. d. 
Published: April 2008

SummaryDetermining the optimal number of staff in a department using a method based on costs.How many men do you appoint in a department of a firm?This number can be determined in an optimal way, if the following data are known:‐ The number of men required per unit of time (may be given as a stochastic quantity).‐ The mean probability of absence per man in the department (due to illness, holidays etc.).‐ Wages per man.‐ Costs (proceeds), if in one unit of time there are less (more) men available than required.Generally the solution will be obtained by an iterative method. However, when the parameters show a certain behaviour it is possible to find the optimum solution by analytical and graphical means.
Some goodness of fit tests for exponential distributions
Authors: Soest J. van 
Published: April 2008

Summary This paper considers tests of exponentiality against unspecified alternatives. The test functions are modifications of those given by Kac, Kiefer and Wolfowitz [Ann. Math. Stat., Vol. 26 (1955) 189–211]. The distributions of these statistics are obtained with the aid of the Monte Carlo method, and the tables may serve to apply a test of exponentiality for the usual levels of significance (sample sizes n≥ 10).A Monte Carlo comparison is also made with competing tests for exponentiality, namely with criteria arising from probability plotting and due to Shapiro and Wilk [(1964) in an unpublished manuscript, but recently described in “Statistical Models in Engineering” by Hahn and Shapiro (Wiley, 1967)], and with tests based on the conditional distribution of total lives and on a likelihood ratio.
De Wet en de kansspelen
Authors: Hamaker H. C. 
Published: April 2008

SummaryIn the Netherlands all gambling is forbidden except in a few cases specially mentioned in the law. Time and again specialists in probability theory or statistics are called upon to testify as experts in lawsuits against law evaders. This paper discusses the part played by the experts in such legal procedures. It is pointed out that according to Dutch jurisprudence there does not exist an exclusive distinction between games of chance and games of skill. A simple declaration by an expert that a given game is largely based on chance suffices to see the game sentenced as against the law. This and various other related questions are discussed in detail and illustrated by examples taken from personal experience in the courts.
Kans en behendigheid
Authors: Hemelrijk J. 
Published: April 2008

Summary “Skill and chance”.According to Dutch law games of chance are forbidden. This leads to the exploitation of all kinds of mechanical plays where skill plays a part, but chance too. Opinions differ about the interpretation of the law, which does not give a clear definition of the kind of plays it wants to forbid. It is not even quite clear whether the distinction between games of chance and games of skill is relevant. In this paper, which is a reaction to Hamaker's paper about the same subject in this issue, the thesis is defended that the distinction is necessary if one does not want the law to imply too much or too little.Rapport S 409 (SP 113) van de Afdeling Mathematische Statistiek van het Mathematisch Centrurn, Amsterdam.
Discussie bijdrage
Authors: Cohen Ir. J. W. 
Published: April 2008

SummaryAn analysis is given of the character of games of chance and games of skill. It is shown that every game is influenced by stochastic effects. Whether a game should be classified as a game of pure skill or as a game of chance depends on the rules of the game, on the evaluation of the outcomes of the game and on the possibilities the player has by applying his skill to cope with the random effects of the particular game situations.
Percentiles and approximations of the sample median over the sample range for samples of size 3, 5, 7 and 9 from a standard normal distribution
Authors: Bouma N. , Vehmeyer A. 
Published: April 2008

SummaryA table of the distribution function of the quotient of sample median and sample range of small samples from the normal distribution is given which is based partly on theoretical results published by L. de Haan and J. Th. Runnenburg, partly on numerical results obtained with Monte Carlo methods. Moreover an approximation of this distribution by Students distributions is introduced.
Invariantie in de schattingstheorie
Authors: Sander P. C. 
Published: April 2008

Summary A number of methods of estimation have been proposed on relatively intuitive grounds. A “best” method does not exist. Sometimes the principle of invariance or, better termed, equivariance is very useful. By use of the group structure on hand it is possible to characterize equivariant estimators.Lezing gehouden op de Statistische Dag 1969.
A fractile programming approach with extreme sample estimates of parameters
Authors: Sengupta J. K. , Sanyal B. C. 
Published: April 2008

Abstract This paper investigates the implications of extreme value estimates of net prices in the objective function of a linear programming problem. Analytically, our approach suggests interesting points of comparison between different measures of sensitivity of a linear programming problem, when a specified fractile of the distribution of profits is optimized.Work done under the National Science Foundation Project GS‐1810–420–21–17 at the Department of Economics, Iowa State University.
The Neyman‐Pearson theory for testing statistical hypotheses
Authors: Schaafsma Willem 
Published: April 2008

SummaryThis is an attempt to write an introduction to some aspects of the present state of the Neyman‐Pearsontheory. The object is to interest the reader who has some knowledge of modem probability theory and statistics. We try to emphasize the main ideas, “unnecessary” mathematics is avoided.In our opinion, the Neyman‐Pearsontheory (or, more generally, the objectivistic approach to statistics) is a vigorous attempt to statisfy some weakened form of the philosophical principle of the “intersubjective verifiability”. This attempt is considered successful in those situations where “various different objectivistic optimum properties are satisfied by the same optimal test”. Unfortunately, these conditions are not satisfied for many situations from actual practice (testing against restricted alternatives, non‐parametric problems). Thus we arrive at a dilemma: for many problems from practice different “optimum” tests are available. There is no easy way out of this dillemma (see the last section).We have tried to emphasize the motivation and to aim at readability while minimizing the overlap with e.g. Lehmann'sbasic textbook. Thus many basic tools are disregarded: exponential families, completeness and sufficiency of statistics and many other subjects are missing, the restrictions by similarity, unbiasedness or invariance are only mentioned. The references constitute an incomplete apology for deleting so many important contributions.
De frequentistische opbouw van de waarschijnlijkheids‐rekening volgens R. von Mises
Authors: Daal J. van 
Published: April 2008

SamenvattingR. von Mises publiceerde zijn frequentistische opbouw van de waarschijnlijkheidsleer voor het eerst in 1919. De daarbij naar voren gebrachte inzichten verschilden zeer van de in die tijd algemeen geaccepteerde ideeén omtrent de grondslagen van de waarschijnlijkheidsleer. Onder invloed van (zowel opbouwende als abrekende) kritieken, alsmede door eigen gewijzigde inzichten, evolueerde zijn theorie zich, via diverse publikaties, tot die, weke wij aantreffen in zijn in 1964 posthuum verschenen, laatste werk.In dit artikel wordt nader ingegaan op de theorie van Von Mises, zoals die in het zojuist genoemde werk behandeld wordt. Hiertoe is het soms nodig in te gaan op vroegere publikaties van zijn hand.In vele boeken en artikelen (zie bijv. Cramer (1966) p. 150 en Hemelrijk (1968) p. 13) worden enige zinnen gewijd aan het feit, dat Von Mises zich met de grondslagen van de waarschijnlijkheidsleer heeft bezig gehouden. Bijna nooit krijgt men echter te lezen, wat hij precies gezegd heeft.
Simplified estimation of parameters in a cauchy distribution
Authors: Raghunandanan K. , Srinivasan R. 
Published: April 2008

SummarySimplified estimators of the location and scale parameters of a Cauchy distribution are constructed along the lines developed by Dixon [3, 4]. Symmetrically censored samples are considered. The efficiency of these estimators is shown to be high enough to make them useful in practice.
Probability distributions of two‐component soil samples
Authors: Stol Ph. Th. 
Published: April 2008

SummaryMixing of sand layers on top of peat soils is achieved by soil improvement machines. The result of the mixing process is studied by taking samples from a vertical cross‐section of the profile. The samples will have various values of the sand to peat volume‐ratio. These values can be plotted in emperical cumulative frequency distributions. The distributions for two types of machines were found to be quite different due to differences of mixing intensities. A method is proposed for the evaluation of the mixing effect expressed in the parameters of theoretical probability distributions of two‐component soil samples. The probability distribution of the volume‐ratios in the sample are derived and their properties are discussed. Moment estimators of the parameters are derived. The theoretical distributions are compared with two experimental results obtained with a mixing rooter and a rotary mixer respectively.
A comparison of two nonparametric k ‐sample slippage tests
Authors: Doornbos R. , Senden W. L. M. M. 
Published: April 2008

SummaryThe tests which are discussed here are Mosteller's k‐sample slippage test for an extreme population [8] and the k‐sample slippage analogue of the Wilcoxon two‐sample test proposed by Doornbos and Prins [3]. A comparison is made between both tests in respect of their consistency against normal, exponential and uniform shifts and against Lehmann‐alternatives. For some small sample sizes the powers of the two tests have been calculated.
The estimation of guaranteed fatigue life under random loading
Authors: Jaroš Frantšek , ŽAludová Agnes H. 
Published: April 2008

Introduction and SummaryOne of the pressing problems of mechanical reliability still requiring a satisfactory solution is that of ensuring the guaranteed fatigue life of a component or structure subject to random dynamic loading. In the past, this problem has generally been solved in technical practice by the choice of a sufficiently large “safety factor” when dimensioning critically stressed parts of a complex structure.Application of probability and statistical methods now offers the possibility of developing a theory of reliability of mechanical systems, where the risk of failure can be expressed as a probability, taking into account effects of random loading processes, which characterize either the functioning of the system itself or external environmental operating conditions.In the following paper we describe one method of approach to the solution of this problem. The solution consists of a combination of the Weibull‐Freudenthal‐Gumbel theory of fatigue estimation using (s̀, N, P) relations, the Palmgren‐Miner hypothesis of linear accumulation of damage and the theory of stationary random processes having a given autocorrelation function or spectral density. Several other stochastic models are discussed in [1]. The subject of this paper was chosen in acknowledgement of the fact that H. C. Hamaker in his applied theoretical work also dealt with a related problem concerning the breaking strength of glass [2].
Lineaire regressie‐analyse, ook bij gegevens in strijd met het model
Authors: van Montfort M. A. J. 
Published: April 2008

Samenvatting Robuuste lineaire regressie‐analyse volgens Andrews (1973) wordt behandeld. Deze methode is bestand tegen enige fouten in zowel de verklarende variabele(n) als in de te verklaren variabele. Zij leverti. een opsplitsing van de waarnemingen in begrijpelijke en onbegrijpelijke bij het gekozen model, en ii. parameterschattingen met nauwelijks verlies aan doeltreffendheid bij Gauss‐residuen ** en met grote winst aan doeltreffendheid bij residuen met langere staart. zulks vergeleken met de bekende kleinste kwadraten procedure, die optimaal is bij Gauss‐residuen.Aan de hand van getallen‐voorbeelden wordt een en ander toegelicht.
Discounted semi‐Markov decision processes: linear programming and policy iteration
Authors: Wessels J. , Nunen J. A. E. E. van 
Published: April 2008

AbstractFor semi‐Markov decision processes with discounted rewards we derive the well known results regarding the structure of optimal strategies (nonrandomized, stationary Markov strategies) and the standard algorithms (linear programming, policy iteration). Our analysis is completely based on a primal linear programming formulation of the problem.
Some models of truck allocation for household refuse collection*
Authors: Panne C. van de 
Published: April 2008

AbstractA number of models is developed for the selection and allocation of trucks for household refuse collection. The models vary from a simple model related to the optimal batch‐size formula to a linear programming model. A minimum‐cost selection is made on the basis of time per pick‐up, weight per pick‐up, driving time from collection area to landfill site, capacity and costs of the relevant truck‐crew combinations and lengths of possible shifts. The models are equally applicable to other house‐to‐house collecting and distributing activities.