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# The 1-st example: MRMC data
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# 1) Fit a Model to MRMC Data
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fit <- fit_Bayesian_FROC( ite = 1111, dataList = ddd )
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# 2) Evaluate Posterior Predictive P value for the Goodness of Fit
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ppp(fit)
# If this quantity, namely a p value is greater,
# then we may say that our model is better.
# Of course, even if p-values is small, we should not ignore our result.
# P value bitch is not so clear what it does and in frequentist methods,
# we experianced p value is bitch with respect to sample size.
# So, in Bayesian context, this bitch might be bitch with respect to ...
# Anyway, but ha....many statisticians like this bitch.
# The 2-nd example uses data named d
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# 1) Fit a Model to Data
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fitt <- fit_Bayesian_FROC( ite = 1111, dataList = d )
#----------------------------------------------------------------------------------------
# 2) Evaluate Posterior Predictive P value for the Goodness of Fit
#----------------------------------------------------------------------------------------
ppp(fitt)
# If this quantity is greater, then we may say that our model is better.
# I made this ppp at 2019 August 25.
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# PPP is problematic
#----------------------------------------------------------------------------------------
# Consider the dataset:
dat <- list(c=c(77,3,2,1), # Confidence level. Note that c is ignored.
h=c(77,97,32,31), # Number of hits for each confidence level
f=c(1,14,74), # Number of false alarms for each confidence level
NL=259, # Number of lesions
NI=57, # Number of images
C=3) # Number of confidence level#'
# Fit a model to the data
fit <- fit_Bayesian_FROC(dat)
# calculate p value
ppp(fit)
# Then we can see that FPF and TPF are far from FROC curve, but p value is not
# so small, and thus in this case, ppp is not the desired one for us.
# In our model, we need monotonicity condition, namely
#
# h[1] > h[2] > h[3] > h[4]
# f[1] < f[2] < f[3] < f[4]
#
# However the above dataset is far from this condition, and it would relate the
# above undesired p value.
# Revised 2019 Sept 7
# Of course it is no need to satisfy this monotonicity precisely, but good data
# should satisfy.
# Since doctor should not wrong (false positive) diagnosis with his high confidence.
# }
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