the national accounts and economic models. Bjerve was President of the International
Statistical Institute from 1971 to 1974, and became a driving force behind the World
Fertility Survey Programme. He died on January 12th, 2004.
B lack, Arthu r ( 1851^1 893): Born in Brighton, UK, Black took a B.Sc degree of the University of
London by private study, graduating in 1877. He earned a rather precarious living as an army
coach and tutor in Brighton, while pursuing his mathematical and philosophical interests. He
derived the
chi-squared distribution
as the limit to the
multinomial distribution
and inde-
pendently discovered the
Poisson distribution
. Black’s main aim was to quantify the theory
of evolution. He died in January 1893.
Blinder ^ Oaxaca method: A method used for assessing the effect of the role of income on the
racial wealth gap. The method is based on a decomposition of the mean interrace difference
in wealth into the portion due to differences in the distribution of one or more explanatory
variables and that due to differences in the conditional expectation function, and the para-
metric estimation of a wealth–earnings relationship by race. [Yale University Economic
Growth Center Discussion Paper No. 873, 2003, pp. 1–11.]
Blinding: A procedure used in
clinical trials
to avoid the possible bias that might be introduced if the
patient and/or doctor knew which treatment the patient is receiving. If neither the patient
nor doctor are aware of which treatment has been given the trial is termed double-blind.If
only one of the patient or doctor is unaware, the trial is called single-blind. Clinical trials
should use the maximum degree of blindness that is possible, although in some areas, for
example, surgery, it is often impossible for an investigation to be double-blind. [Clinical
Trials in Psychiatry, 2nd edition, 2008, B. S. Everitt and S. Wesseley, Wiley, Chichester.]
Bliss, Chester Ittner (18 99^1979): Born in Springfield, Ohio, Bliss studied entomology at
Ohio State University, obtaining a Ph.D. in 1926. In the early 1930s after moving to
London he collaborated with Fisher, and did work on
probit analysis
. After a brief period
at the Institute of Plant Protection in Leningrad, Bliss returned to the United States
becoming a biometrician at the Connecticut Agricultural Experimental Station where he
remained until his retirement in 1971. He played a major role in founding the International
Biometric Society. The author of over 130 papers on various aspects of
bioassay
, Bliss died
in 1979.
BLKL algorithm : An algorithm for constructing
D-optimal designs
with specified block size.
[Optimum Experimental Designs, 1992, A. C. Atkinson and A. N. Donev, Oxford Science
Publications, Oxford.]
Block: A term used in experimental design to refer to a homogeneous grouping of experimental units
(often subjects) designed to enable the experimenter to isolate and, if necessary, eliminate,
variability due to extraneous causes. See also randomized block design.
Block, Borges and Savitsmodel: A model used for recurrent events in reliability and engineer-
ing settings. In this model a system (or component) is put on test at time zero. On the
system’s failure at some time t, it undergoes a perfect repair with probability p(t)oran
imperfect repair with probability qðtÞ¼1 pðtÞ. A perfect repair reverts the system’s
effective age to zero, whereas a minimal repair leaves the system’s effective age unchanged
from that at failure. [Journal of Applied Probability, 1985, 22, 370–85.]
Block clustering: A method of
cluster analysis
in which the usual multivariate data matrix is
partitioned into homogeneous rectangular blocks after reordering the rows and columns.
The objectives of the analysis are to identify blocks or clusters of similar data values, to
identify clusters of similar rows and columns, and to explore the relationship between the
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