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Box-Cox Linearity Plot Top Prev Next

Sample Box-Cox linearity plot

  • Question:
    What is best transformation of Y so that T(Y) vs. X is most linear?

  • Definition:
    Vertical Axis : Correlation coefficient of T(Y) and X
        where T(Y) is the Box-Cox transformation of Y
    Horizontal Axis: Box-Cox power transformation parameter (lambda)

  • Interpretation/Conclusion:
    Best transformation is lambda = 0.6. Note that the square root transformation (lambda = 0.5) is a reasonable choice in this case.

  • NIST/SEMATECH Handbook Chapter:
    1. Exploratory Data Analysis
    4. Process Modelling

  • References:
    NIST/SEMATECH e-Handbook of Statistical Methods, Box-Cox Linearity Plot, 6/2003.

    Box and Cox (1964), "An Analysis of of transformations," Journal of the Royal Statistical Society, Series B 26 (2): 211–252.

Dataplot Command: BOX-COX LINEARITY PLOT Y X
Dataplot Code:
SKIP 25
READ BERGER1.DAT Y X
TITLE BOX_COX LINEARITY PLOT
LABEL CASE ASIS
Y1LABEL Correlation Coefficient
X1LABEL Alpha
BOX-COX LINEARITY PLOT Y X

Dataplot Reference Manual Documentation for BOX-COX LINEARITY PLOT


Date created: 06/05/2001
Last updated: 02/13/2023

Please email comments on this WWW page to alan.heckert@nist.gov.