The Estimation of Blood Platelet Survival

Summary

The characteristics of experimental error in measurement of platelet radioactivity have been explored by blind replicate determinations on specimens taken on several days on each of three Walker hounds.

Analysis suggests that it is not unreasonable to suppose that error for each sample is normally distributed ; and while there is evidence that the variance is heterogeneous, no systematic relationship has been discovered between the mean and the standard deviation of the determinations on individual samples. Thus, since it would be impracticable for investigators to do replicate determinations as a routine, no improvement over simple unweighted least squares estimation on untransformed data suggests itself.

• References

• 1 Bartlett M. S. 1937; Properties of sufficiency and statistical tests. Proceedings of the Royal Society A 160: 268.
• 2 Fisher R. A. 1958. Statistical Methods for Research Workers. Thirteenth edition.. Oliver and Boyd; London p. 99:
• 3 Hartley H. O. 1940; Testing the homogeneity of a set of variances. Biometrika 31: 249.
• 4 Kendall M. G. 1948. Rank Correlation Methods. Charles Griffin and Co Ltd.; London:
• 5 Kendall M. G, and Stuart A. 1958. The Advanced Theory of Mathematical Statistics. Vol.1 p. 193. Charles Griffin and Co. Ltd.; London:
• 6 Murphy E. A. 1971; The estimation of blood platelet survival. III. The robustness of the basic models. Thrombosis et Diathesis Haemorrhagica 26: 431.
• 7 Murphy E. A, and Francis M. E. 1969; The estimation of blood platelet survival. 1. General principles of the study of cell survival. Thrombosis et Diathesis Haemorrhagica 22: 281.
• 8 Murphy E. A, and Francis M. E. 1971; The estimation of blood platelet survival. II. The multiple hit model. Thrombosis et Diathesis Haemorrhagica 25: 53.
• 9 Snedecor G. W, and Cochran W. G. 1967. Statistical Methods applied to Experiments in Agriculture and Biology. Sixth Edition.. Iowa State College Press; Iowa: 84.