摘要:

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 Septemb

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00400.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

SummaryA survey of the transactions and discussions at the Second Congress of the Biometric Society held at Geneva from the 30th of August to the 2nd of September 1949.Genève, 30 Augustus‐2September 19

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00401.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

SummaryThe amount of inspection required in sequential sampling.Sequential sampling plans as developed by Barnard3)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>5are 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 by4Standard Sequential Sampling Plans, for which Smin=2, 3, 4and5respectively.In table I the0,05producer's and consumer's risk points (pland 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 pi(the percetage of defectives in the batch).But even when H, b, and piare 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 the10, 20, 30, 40and50%points of these probability distributions are represented in figs5–8.The sample sizes of single sampling plans possessing the same operating characteristics were found to be approximately6n, 12n, 22n, and35n respectively, and from figs5–8it 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

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00402.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

SummaryA note on the inequality of Camp and Meidell.This paper describes a simple and illustrative proof of the inequality of Camp and Meidell according to a line of argument originally due to Dr B.‐H. d e Jong. The conditions to be satisfied in order that the inequality shall be applicalbe are discussed, while in a final section some practical applications are considere

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00403.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

SummarySystematic and random errors in reading the position of a pointer on a scaleIn a prèvious article1)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

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00404.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Summary(The average outgoing quality limit for single sampling plans with c = o). The average outgoing quality limit occurs atPi= 1/(1 + n)Its exact value is given by(6)and two approximations by(7)and(8),of which the more simplified formula(8)gives better results(see Table 1).

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00405.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY

摘要:

Book reviewed in this article:Statistics for Economists, door R. G. D. AllenA first course in mathematical statistics, door C. E. WeatherburnProbability theory for statistical methods, door F. N. DavidStatistical Methods in Research and Production, onder redactie van O. L. DaviesStatistiek, O. Bakker

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1949.tb00406.x

出版商:Blackwell Publishing Ltd    

年代:1949

数据来源: WILEY