bluuebunny/crossref_metadata_2025_split huggingface dataset:
STATISTICA: De Overschrijdingskans
Authors: Bok S. T. 
Published: April 2008

SummaryIf we want to check a hypothesis by numbers, obtained from measuring or from counting in a random sample, practically always a difference will be found between these numbers and those, derived from that hypothesis‐Such a difference may be caused by faults in the hypothesis or by factors which we do not want to analyse such as faults in the measuring or the influence of the sampling or influences acting together with the one regarded in our hypothesis.The theory of statistics shows a way to estimate the chance that such another cause would result into a difference equal to or large than the one actually found. If in a given case this “chance of surpassing” is found to be small, we have to reject the hypothesis concerned. The smaller this chance is the larger is the likelihood of that rejection; it is the estimate of the likelihood of each statistical conclusion.
Statistische hulpmiddelen bij de. kwaliteitsbaheersing II1
Authors: Enters J. H. 
Published: April 2008

SummaryAn exposition is given of the methods of statistical quality control of a flow of products from a particular production process in cases where quality is being measured by the number of defectives in a sample. Examples are given of the way in which this is being done in cases where go — not go gauges can be applied.
Eenige statistische opmerkingen over verpakkingsen doseeringsproblemen
Authors: Sittig J. 
Published: April 2008

SummaryIn packing powders, fluids and the like in mass production there are three frequency distributions of weights, viz. net weights, gross weights and tare weights. It is shown that by elementary statistical methods the standard deviation of one of these three distributions may be found by analysing the other two.The excisting correlation, e.g. between net weights and tare weights, can be found by the same methods.
Typologie van den statisticus Hoe men hem ziet en hoe hij
Authors: van der Burg Drs A. R. 
Published: April 2008

SummaryIn the popular conception the statistician is a man who collects and groups figures which he publishes in the form of tables and graphs. The real statistician in the modern sense of the word, i.e. the man who does not collect the material but analyses it and draws his conclusions from it, is as yet practically unknown to the general public. It is desirable that more publicity should be given to the characteristic qualities required for this calling, so that those most fitted for i may be drawn towards it.The aspiring statistician should be taught to think in statistical terms and not along functional or determinist lines, as the mathematician does. The statistician is only interested in individual phenomena insofar as they enable him to draw conclusions of a more general character out of a certain amount of isolated cases. A true sense of proportion is very important as it plays a major part in the framing, the working out and the conclusions to be drawn from the solution of the problems. As the sphere of his activities is so extensive, the statistician should be able to adapt himself quickly to new situations.Those who are endowed with these varying talents can rely on finding a very useful task as a statistician.
Drie soorten statistiek in de natuurkunde?
Authors: Schwarz N. 
Published: April 2008

Summary  (Three kinds of statistics in physics).A simplified derivation is given of the energy‐distribution of Maxwell‐Boltzmann, Bose‐Einstein and Fermi‐Dirac. The importance and the application of these laws are considered, and the fundamental hypotheses, on which they are based are mentioned.It is shown that only one sort of statistics is used, but that the statistical method is adapted in each case to the special physical properties of the particles, to which this method is applied.
De kosten van levensonderhoud te ‘s‐Gravenhage in December 1946
Authors: Vermeulen A. J. M. 
Published: April 2008

Summary  (The minimum costs of living at The Hague in December 1946).Standards are given for the minimum costs of living in December 1946 for families of different composition and different gross wages.Fig. 1 shows the family income as a percentage of the necessary expenses.In Fig. 2 a specification is given of the total expenses for families with respectively 0, 2 and 4 children and for single persons not living with their families.The expenses are divided into: A. taxes and insurance, B. costs of food, C. costs of housing, D. repairs of clothes etc., E. procuring of new clothes and household utilities.SamenvattingIn onderstaand overzichtje geven wij nu voor ieder gezinstype het inkomen, excl. kinderbijslag, dat nodig is a. om de minimaal noodzakelijke kosten te kunnen dekken en b. om bovendien ook de boven beschreven niet‐minimaal noodzakelijke uitgaven te kunnen doen.Wanneer we de niet‐minimaal noodzakelijke kosten buiten beschouwing laten en alleen de dekkingspercentages bezien, zoals dezr uit fig. 1 af te laten zijn, dan zien we, dat ondanks de onlangs verhoogde kinderbijslag ook thans nog vele gezinnen niet in staat zijn om aan hun meest dringende verplichtingen te voldoen.Dat dit aanleiding geeft tot zeer ongewenste toestanden zal iedereen duidelijk zijn. In vele gezinnen toch zullen bonnen, welke niet gerealiseerd kunnen worden, te gelde gemaakt worden. Dit geldt in het bijzonder voor snoepbonnen, extra bonnen voor kinderen (zoals voor sinaasappelen en eieren) enz.Dit rapport wil niet de pretentie hebben aanwijzingen te geven hoe hierin verandering gebracht kan worden. Wij stelden ons slechts ten doel door het publiceren van concrete gegevens de aandacht te vestigen op de financiele nood, waarin duizenden zich bevinden ten gevolge van de wanverhouding tussen lonen en prijzen.Daarnaast meenden wij goed te doen door richtlijnen te geven voor de besteding van het inkomen, in het bijzonder voor zover dit betreft de posten voeding en nieuwe aanschaf.Men dient echter steeds voor ogen te houden, dat deze richtlijnen zéér ruim genomen moeten worden. Er zullen vele factoren zijn, die een afwijking van de gegeven verdeling nodig of gewenst zullen maken. Zo zal het bij de uitgaven voor nieuwe aanschaf van belang zijn of men al dan niet oorlogsslachtoffer is.Voorts zal men ook rekening dienen te houden met een verhoging van de post voeding bij toekenning van extra‐rantsoenen voor langdurige, zware of zeer zware arbeid.Ten slotte verdient het vermelding, dat behalve van de in het literatuur‐overzicht genoemde publicaties, speciaal voor de post voeding gebruik werd gemaakt van gegevens van het Voorlichtingsbureau van de Voedingsraad te s‐Gravenhage.
Weersverwachting op lange termijn
Authors: Visser Prof. Dr S. W. 
Published: April 2008

Summary  (Long range weather forecasts. II The correlation ellipses).The description of the method for determination of long range weather conditions, as presented by the Kon. Ned. Meteorologisch Instituut at De Bilt, is continued.The formulae lead to the construction of socalled correlation ellipses which are of great use to find the best new variables to be added in order to improve correlation. The calculus is very simplified by this method, which deals with the complicated correlation phenomena; reliable results can only be obtained by careful application.
Naschrift bij het artikel van Mr W. H. Somermeijer
Authors: Enters J. H. 
Published: April 2008

Summary  (Post scriptum by Mr. Enters).Spearman s saturation coefficient which is computed from correlation coefficients between series of measurements by several inspectors may be used to express the capacity of these inspectors for massinspection only if a systematic bias in their results may assumed to be not existing or is accounted for. As an example it is shown that the differences between the means of the measurements by the inspectors mentioned in the previous article (Statistica I, pag. 40) are not significant.
De bepaling van de nauwkeurigheid, waarmede metingen of beoor‐delingen worden verricht.
Authors: Posthumus Dr Ir G. 
Published: April 2008

Summary  (Discussion of the accuracy of measurements and judgments).In this paper a Summary is given of the methods, which are used or can be used to determine the accuracy, with which measurements, which can be expressed in concrete units (lengths, weights, percentages etc.), can be made.An account is also given of a method, which can be used, when expression in concrete units is not possible (e.g. grading the odor or taste of butter or wine, judging the achievements of pupils by means of test‐work).
Een systematische vergelijking van de statistische eigenschappen van hedendaagse steekproef‐schema's1
Authors: Hamaker H. C. 
Published: April 2008

Summary  (A systematic comparison of the statistical properties of present‐day sampling schemes).A survey of various sampling schemes, carried out with the aid of the, random walk diagram, ‘leads to the conception that it must be possible to effect the same degree of inspection by the application of different schemes. The degree of inspection of a scheme is contained in its, operating characteristic’, which is specified by two constants viz:its centre q0, for which P = 1/2, and its slope s in this point, defined by s= ‐(dP/dq)q=q0.It is shown that, if the operating characteristics of two different sampling schemes possess the same values of q0 and s, the two characteristics are almost completely coincident. Thus two sampling schemes having the same q0 and s will give identical inspection performances, and are consequently defined as, equivalent. ‘And by comparing the average sample sizes of equivalent schemes we may compute their relative efficiency’. For each set of values q0 and s it is possible to construct a single sampling scheme possessing these characteristics. Hence to any scheme whatever there will correspond an, equivalent single sampling scheme, and, by adopting the single sampling scheme as a standard of reference, we may arrive at a general definition of efficiency.By the introduction of q0 and s the formulae relating to the sequential sampling scheme are greatly simplified, and for each set of values q0 and s there is one corresponding sequential scheme.By discussing a particular example of the double sampling scheme it is shown that the methods developed in this paper can successfully be applied to a systematic treatment of the variety of schemes now in existence.
Hyperbolische foutenwet
Authors: Brethouwer D. H. G. 
Published: April 2008

Summary  (The hyperbolic law of errors).In the first chapter some general questions concerning the error distribution are discussed and the deduction of the hyperbolic error distribution is given.Next the properties of this distribution are shown and some fundamental data (standard deviation etc.) are determined.Finally the hyperbolic error distribution is compared with the Gaussian distribution and tested in practice.
Toevals‐frequenties, een hulpmiddel bij de constructie yan kunstmatige steekproeven van grote omvang
Authors: Hamaker H. C. 
Published: April 2008

SummaryThe construction of large‐size random samples by means of random sampling numbers in the usual way requires much tedious labour. This paper describes a short‐cut technique by which artificial samples, of say 500 or 1000, can be obtained in about one tenth of the time. Use is made of previous records of the frequencies of two‐digit random sampling numbers; these are called the random sampling frequencies'.
Statistisch onderzoek van contrôle‐analyse cijfers: (De verdeling van het droge stofgehalte van het brood tijdens de tweede wereldoorlog)
Authors: Hekker Ir Th. , Straub Ir J. 
Published: April 2008

Summary  (Statistical investigation of the distribution of data for the solids of bread (in loaves analysed in the Food Inspection Laboratory in Amsterdam))The distributions of the data of the solids of bread as analysed during the years of the war are investigated. The means and the standard deviations are calculated, also χ2, kurtosis and skewness supposing the distributions to be normal. An example of calculation is given in table I. Actual numbers for different years are given in table II and in table III. The distributions were tested on normality because former investigations showed that the distribution of under survey prepared loaves did not deviate significantly from the normal.It is found that generally the investigated distributions cannot be regarded as normal. Though symmetric they show leptokurtosis and the χ2‐test for the goodness of fit of normal equation gives values of P 0,01 (or a little more). Similar distributions were found by Clancey1) in his investigation of numbers of chemical analyses of industrial products (about 10% of the distributions showed this shape, some 10% were truncated leptokurtic curves) and by us for the fat percentage of meals from the governmental eating‐houses. The distributions are represented on probability‐paper. This way of representing results gives a clear view of the variations of the mean and the standarddeviation in the course of the years (fig. 1). The deviations of the shape of the normal straight line on probability paper by special causes is investigated (fig. 3, fig. 4, fig. 5, fig. 6 to be compared with fig. 2). With this “spectrum” of possibilities of deviations from the normal distribution in mind the special cause for the leptokurtic shape in our special case has been discussed.
Superpositie van twee frequentieverdelingen
Authors: Sittig J. 
Published: April 2008

Summary  (Superposition of two frequency distributions)Notation:n: number of observationsM: arithmetic means̀: standard deviationμr: rth moment coefficientβ1: coefficient of skewnessβ2: coefficient of kurtosis.The suffixes a and b apply to the component distributions. The suffix t applies to the resulting distributions. The problem: Given the first r moments of two frequency distributions (to begin with μ0). Find the first r moments of the distribution resulting from superposition of the two components (r≥5).Formulae [1]. … [5] (§3) give the results in their most general form up to μ4.Some special cases are treated in § 4, and eight different cases of superposition of two normal distributions in § 5.In § 6 some remarks are made about the reverse situation, i.e. the splitting into two normal components of a combined frequency distribution.
De bewerking van de resultaten van veldproeven door herleiding van de opbrengstcijfers in beide richtingen van het proefveld
Authors: Stoffels Ir A. 
Published: April 2008

Summary  (The treatment of the results of field experiments by reducing the yields in two directions)Ir J. J. Dijkveld Stol has shown that good results have been obtained by reducing the yields of field experiments both in columns and in rows.The mathematical foundation of this method is discussed in the preceding article and it is shown, that the method gives good results if the same supposition may be made as necessary for the application of the methods of Fisher, Knut Vik and the method of the differences.The variance s̀ of Dijkveld Stol's method is identical with Fisher's error variance.
De ruis in radiobuizen ais statistisch verschijnsel*
Authors: Hamoker H. C. 
Published: April 2008

SummaryNoise in radio valves as a statistical phenomenon.If an electric current is interpreted as. the passage of a certain number of electrons per second, it is evident that such a current will be subject to statistical fluctuations. These fluctuations, commonly designated as “noise”, limit the maximum amplification applicable in radio reception. Some of the fundamental principles of noise formation are treated in this article from a statistical point of view. The formation of noise, noise suppression by space charge, current‐distribution noise, and noise due to secondary emission are successively discussed.
Anthropologische opmerkingen over anthropo‐sociologische feiten *
Authors: de Froe A. 
Published: April 2008

SummaryAnthropological notes on anthropo‐sociological data.Frequency distributions and correlations observed by van Ettinger and Sittig 1) in their extensive research concerning the body measurements of Dutch women, are here discussed from an anthropological point of view. In particular it is pointed out that a certain parallelism can be traced between the correlations of certain classes of measurements of the human skull and the correlations of analogous classes of measurements taken on the human body.
Een verband tussen zonnevlekken en extreme winters
Authors: Visser S. W. 
Published: April 2008

SummaryA relation between solar activity and extreme wintersThe well‐known II‐years period in solar activity is eliminated by computing moving averages of relative sunspot numbers over II‐year intervals. The averages thus obtained reveal a ‘long period’ probably of about 89 years. By subtracting the averages from the original figures reduced sunspot numbers are obtained which represent the normal II‐years fluctuations after elimination of the long period.Standard deviations of winter temperatures have been computed in a similar fashion for moving II‐year intervals, and these standard deviations have been plotted against the average sunspot numbers in figs. 1 and 2, crosses referring to the years before 1831 and dots to the years after. Both at De Bilt and at Prague the observations from 1831 onwards exhibit a pronounced positive correlation, with correlation coefficients of +0.82 and +0.74 respectively. No such correlation can be detected in the earlier observations, which the author is, however, inclined to ascribe to the inaccuracy and incompleteness of the data collected in these early periods. As shown by fig. 3 no correlation does exist between the temperature deviations and the reduced sunspot numbers.It must be concluded that extreme winters occur during the peak solar activities of the long solar period; the normal II‐years period is of no consequence.From a statistical point of view these results are noteworthy: the standard deviation shows systematic variations which are doubtless of physical origin. Statisticians are advocated not to lose sight of the physical background when applying statistical methods to physical phenomena.
Het “Internationaal sfatisrisch Instituut” en het Congres te Bern van 5–10 Sept. 1949
Authors: Hamaker H. C. 
Published: April 2008

SummaryThe ‘International Statistical Institute’ and its session at Bern from 5 to 10 September.A general survey Concerning the organisation and activities of the ‘International Statistical Institute’ and the papers contributed and discussed at its 26th session held at Bern from 5 to 10 September 1949.
Het aantal noodzakelijke waarnemingen bij toepassing van voortschrijdende steekproeven
Authors: Enters J. H. 
Published: April 2008

SummaryThe amount of inspection required in sequential sampling. Sequential sampling plans as developed by Barnard
3)
are most easy to apply in industrial quality inspection if (in Barnard's notation) the ‘hand cap’ H and the ‘penalty’ b are so adjusted that Smin= H/n = a positive integer, n = b+1 being the size of the successive samples. Sequential sampling plans of this type for which Smin> 5 are not of great interest, because by their extreme severity they necessitate the inspection of too great a number of items. This paper presents the results of computations concerning the amount of inspection required by 4 Standard Sequential Sampling Plans, for which Smin= 2, 3, 4 and 5 respectively. In table I the 0,05 producer's and consumer's risk points (pl and p2) of the operating characteristics of these sampling plans are given for n = 10, 15, 20, …. 100. It may be shown that the products np1and np2tend to a limit as n→∞. When setting up a sequential inspection plan it is also necessary to be informed about the amount of inspection that will be involved. The average amount of inspection is a function of H, b, and p
i (the percetage of defectives in the batch). But even when H, b, and pi are constant the actual amount of inspection in a particular case may differ considerably from the average and may vary within a wide range; hence it is of importance to know its probability distribution. Assuming a Poisson distribution for the number of defectives in a sample, the probability that a sequential sampling plan will necessitate a given amount of inspection will be a function of the product npi. For the four standard plans under consideration the 10, 20, 30, 40 and 50%points of these probability distributions are represented in figs 5–8. The sample sizes of single sampling plans possessing the same operating characteristics were found to be approximately 6n, 12n, 22n, and 35n respectively, and from figs 5–8 it will be seen that the actual amount of inspection in sequential sampling may considerably exceed the sample size of these equivalent single sampling plans, particularly in the region np1 < npi < np2. As these extreme values may occasionally lay a heavy load on the inspection department it is desirable to curtail sequential sampling by setting an upper limit to the number of items that are to be examined. The effect on the operating characteristics of truncating the standard sequential plans after Smax samples of n items each have been drawn, is illustrated in figs 9–12. These show that if in the four cases under consideration Smax is fixed at 6, 12, 22 and 35 respectively, the amount of information lost by truncating is relatively small. The resultant truncated standard sequential plans can be condensed into very simple precepts which are easily learnt by heart by the quality inspector and have proved of great practical convenience.
Systematische en toevallige fouten bij het aflezen van de stand van een wijzer op een school *
Authors: Homaker H. C. 
Published: April 2008

SummarySystematic and random errors in reading the position of a pointer on a scaleIn a prèvious article 1) V. Varangot has recorded the readings by 40 different persons of ten different positions of a pointer, the actual positions being known. He has pointed out certain discrepancies in determining according to different criteria who is the “best” estimator.In the present paper Varangot's data are subjected to a further analysis. It is shown that the discrepancies are mainly the result of the existence of both systematic and random errors. If these are not clearly distinguished discrepancies as observed may always be expected. When, on the other hand, both types of error occur together it is very difficult, if not impossible, rigorously to decide who is the “best” estimator. Spearman's criterion based on correlation coefficients is shown to be unsatisfactory. Finally the order of magnitude of systematic and random errors in Varangot's data are deduced by a‘ regression analysis. A brief abstract of some further papers on this subject is given at the end.