摘要:

It is argued that no simple rule can exist for determining the size of a comparative experiment. In general, estimation of differences calls for higher precision than testing them. Also, with a polynomical partition an experiment well able to show a linear effect may be too small to show an important quadratic effect. Similarly, with a factorial partition a larger experiment may be needed to study an interaction than a main effect.

ISSN:0266-4763    

DOI:10.1080/02664768900000001

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

Taguchi methods are currently attracting much attention, and certain cavalier interpretations of mean squares in saturated fractional designs have recevied criticism. After two examples illustrating the problem, some procedures are tentatively proposed for improving such analyses, but there is scope for refining these methods, and for research into the general problems of using designs with no independent estimate of experimental error.

ISSN:0266-4763    

DOI:10.1080/02664768900000002

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

A Second-order Latin cube of size n x n x n can be used as the design for an experiment in three space dimensions, with the three sets of layers used as three sets of blocks. The n2 treatments are then orthogonal to the main effects X, Y and Z of the blocking systems. Particular interest attaches to second-order Latin cubes whose treatments are an n x n factorial set, with the main effects A and B of the treatment factors orthogonal to the interactions XY, XZ and YZbetween pairs of blocking systems. This note describes such designs where components of the interaction AB are each totally confounded with one of XY, XZ and YZ. Cubes with n = 4 are then described where components of A, B and AB are each partially confounded. Finally, a defective design with n = 4 is described, to illustrate the need for care in composing designs for three dimensions.

ISSN:0266-4763    

DOI:10.1080/02664768900000003

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

Several methods have been suggested, in the literature, to detect influential observations from the data fitting usual linear model y=X***+***, ***∽N(0, ***2I). Recently, Chatterjee & Hadi (1986) have reviewed most of these available methods and described the inter-relationships between them. In this article, we extend some of these methods to the case of multivariate regression data. We consider several data sets to illustrate the methods.

ISSN:0266-4763    

DOI:10.1080/02664768900000004

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

Procrustes analysis is applied to three different data sets. From this, it is inferred that the uncritical use of this technique can be highly misleading. It is suggested that an examination of the internal structure of the data is needed to clarify the results and one form of such examination is used as an illustration in the text.

ISSN:0266-4763    

DOI:10.1080/02664768900000005

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

In this paper we assess a marking scheme for the test for logical order in English language testing. This is achieved by considering the potential misclassification of students due to guessing. The distribution of scores under the hypothesis of random selection is derived and the asymptotic distribution is shown to be Poisson with a mean of unity. Recommendations are given for selecting the number of sentences in the test for logical order.

ISSN:0266-4763    

DOI:10.1080/02664768900000006

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

In this article the fitting of ARIMA models to time series relating to the births at Edendale Hospital in Natal, South Africa, over a 16-year period is discussed. The model (011)X(011)12 provides andexcellent fit to the monthly totals of mothers delivered but serious discrepancies between estimates of the moving average parameters obtained by the method of unconditional least squares using various statistical computer packages were observed. These can be ascribed to the fact that certain of the packages use the method of backcasting to calculate the unconditional sum-of-squares function in the estimation procedure and this approach breaks down for values of the moving average parameters close to the invertibility boundary. A simulation study to compare the different methods of estimation for the model (011) X (011)12 and to assess the seriousness of discrepancies in the ULS estimates is described. ARIMA models which provided the best fit to the series of monthly totals of caesarean sections performed, breechs births and instrumental deliveries are non-seasonal and reflect a dependence of present on past observations. In contrast the series involving stillbirths and neonatal deaths are white noise indicating that perinatal deaths are random events.

ISSN:0266-4763    

DOI:10.1080/02664768900000007

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

Identification of the HLA system is important in anthropological and immunological studies. This paper proposes a simple index typing method to perform the assignment of HLA serological data. It is parsimonious and able to deal with the data of cross-reacting antigens and ill-defined sera. The method is illustrated by an example of the application of the Chinese HLA-A system in Taiwan. A general FORTRAN program for analysing the typing process is available on request from the first author.

ISSN:0266-4763    

DOI:10.1080/02664768900000008

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

In this paper an attempt has been made to obtain a systematic method of estimating the missing values in experimental designs. When the observations are missing in a particular pattern (in RBD and LSD) explicit expressions are given for the estimators of the missing values. This procedure is compared with Yate's iterative procedure by numerical examples.

ISSN:0266-4763    

DOI:10.1080/02664768900000009

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor

摘要:

Designing multiple-deferred state MDS-1(0, 2) sampling plans indexed by Acceptable Quality Level (AQL) and Limiting Quality Level (LQL) is discussed. Tables are presented using which, one can select MDS-1 (0, 2) plan involving minimum risks.

ISSN:0266-4763    

DOI:10.1080/02664768900000010

出版商:Carfax Publishing Company    

年代:1989

数据来源: Taylor