Blood enzymatic activity
This dataset concerns the distribution of enzymatic activity in the blood, for an enzyme involved in the metabolism of carcinogenic substances.
data(enzyme)
enzyme includes the values of the urinary metabolic ratio of 5–acetylamino–6–formylamino–3–methyluracil to 1–methylxanthine (AFMU/1X) after oral administration of caffeine.
This is a classic example for determining the number of modes.
Obtained from the Supplementary material of Richardson and Green (1997), available in http://www.stats.bris.ac.uk/~peter/mixdata.
Bechtel, Y. C., Bonaiti-Pellie, C., Poisson, N., Magnette, J. and Bechtel, P. R. (1993). A population and family study N–acetyltransferase using caffeine urinary metabolites. Clinical Pharmacology and Therapeutics, 54, 134–141.
Richardson, S. and Green, P. J. (1997). On Bayesian analysis of mixtures with unknown number of components (with discussion). Journal of the Royal Statistical Society, Series B, 59, 731–792.
data("enzyme")
# It can be seen that there are two groups in this dataset
# Via exploratory tools
sizer(enzyme,bws=c(0.03,1))
modetree(enzyme,bws=c(0.02,1),logbw=TRUE,addplot=TRUE,col.lines="white")
#Via mode testing
modetest(enzyme)
## Not run:
modetest(enzyme,mod0=2)
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.