摘要:

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 frequen

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1948.tb00365.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Summary (Possibilities and Difficulties in Applying Sequential Sampling)The application of sequential sampling schemes may be much simplified by chasing H and b (in Barnard's notation)in such a way that H/(b+ 1) = integer and (b + 1) = integer. A decision to accept can now be taken only after each (b + 1) items and samples of (b + 1) items may therefore be chosen from the batch.A handicap of H/(b + 1) points is now allowed to the batch. One point is added to the score whenever no defectives are found in the sample; 0, 1, 2, points are subtracted whenever respectively 1, 2, 3. … defectives are found in a sample. The acceptance boundary is 2H/(b + 1) points; the rejection boundary is 0 points.For given 1 in 20 producer's and consumer's risk points (p1%and p2%),values of H and b are given in table 1 and fig

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1948.tb00366.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

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 b

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1948.tb00367.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY

摘要:

Book reviewed in this article:Dr Ir A. Vondeling, De Bedrijfsvergelijking in de landbouwDr W. Sleumer Tzn, Elementen van het groepsleven, Inleiding tot de sociografie en de sociologieDr Ir M. G. Ydo, Plezier in het werk. Verhandelingen van het Instituut yoor Praeventieve Geneeskunde X, 1947

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1948.tb00368.x

出版商:Blackwell Publishing Ltd    

年代:1948

数据来源: WILEY