The comparative efficiency of the X and R Charts and L-S chart for statistical quality control

  • P.V. Krishna Iyer Defence Science Laboratory, Ministry of defence, New Delhi.
  • M.N Bhattacharya Defence Science Laboratory, Ministry of defence, New Delhi
Keywords: Quality control, Statistics

Abstract

This paper deals with the comparative efficiencies of the X and R charts and the L-S chart (L being the largest and S the smallest value of the sample) from the theoretical and practical points of view. It has been found that in practice the corrective steps suggested by both tallied almost exactly. From theoretical points, when standard deviation varies, the L-S chart is almost as efficient as the X and R charts, but with the variation in the mean the relative efficiency of the L-S chart comes down appreciably as the X and R charts, but with the variation in the mean shifts more and more from the original value

Author Biographies

P.V. Krishna Iyer, Defence Science Laboratory, Ministry of defence, New Delhi.
Defence Science Laboratory
M.N Bhattacharya, Defence Science Laboratory, Ministry of defence, New Delhi
Defence Science Laboratory,

References

Howell, J.M. (1949): “Control chart for largest and smallest values” Ann. Math. Stat., 20, 305.

Krishna Iyer, P.V. and Bhattacharya, M.N. (1953) “lecture notes on statistical quality control and sampling inspection” (restricted).

Pearson, E.S. (1945): “ the probability integral of the range in samples of n observations from a normal population” Biometrika, 32, 301.

Sealy, E.H. (1945) : “First guide to quality control for engineers” His majority’s Stationary office,

London.

Stevens, W.L. (1948): “Control by gauging” J. Roy. Stat. Soc., B, 10, 54.

Tippet, L.H.C. (1925): “On the extreme individuals and the range of sample taken from a normal population.” Biometrika, 17, 365.

Published
2013-01-01
How to Cite
Krishna Iyer, P., & Bhattacharya, M. (2013). The comparative efficiency of the X and R Charts and L-S chart for statistical quality control. Defence Science Journal, 4(2), 55-66. https://doi.org/10.14429/dsj.4.3702
Section
General Papers