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I am trying to evaluate the fit of my mixture model by overlaying the histogram of the original data with three beta distributions. I am using ggplot2 for visualization, but I am facing issues with the overlay.

The histogram of the original data is showing up as expected, but the beta distributions are squeezed on the left side and disconnected. I have tried various modifications in the code but still couldn't resolve the issue.

Can anyone help me with creating a proper overlay of histogram and multiple beta distributions in ggplot2 to evaluate the fit of my mixture model?

Below you can see my code for example.

beta1 <- dbeta(C1, alpha[1], beta[1])
beta2 <- dbeta(C2, alpha[2], beta[2])
beta3 <- dbeta(C3, alpha[3], beta[3])

vaf_hist <-data.frame(table(vaf_trim))
vaf_hist$density <- vaf_hist$Freq /length(vaf_trim)* 100


'''
alpha <- c(5.294863, 23.065857, 29.756515)
beta <- c(93.69862, 75.92762, 69.23697)
'''

plot <- ggplot() + 
  # geom_bar(data = vaf_hist, aes(x=vaf_trim, y = Freq), position="stack", stat="identity") + 
  geom_bar(data = vaf_trim, position = "stack", stat = "identity") +
  geom_line(aes(C1, beta1, color = "Cluster1"),
            size = 1.2, position="stack", stat="identity",
            linetype = "dotdash", )+
  geom_line(aes(C2, beta2, color = "Cluster2"),
            size = 1.2, position="stack", stat="identity",
            linetype = "dotdash")+
  geom_line(aes(C3, beta3, color = "Cluster3"),
            size = 1.2, position="stack", stat="identity",
            linetype = "dotdash")+
  labs(title = "Mixture of 3 Betas",
       x = "Variant Allele Frequency",
       y = "Density",
       colour = "Beta Distr",
       caption = "DPMM with simulated data()")

plot

And here's the image I got. enter image description here

enter image description here

Here's the example of data used. vaf_hist

vaf_trim Freq      density
1      0.02  930  2.175438596
2      0.03 3788  8.860818713
3      0.04 4743 11.094736842
4      0.05 4973 11.632748538
5      0.06 3995  9.345029240
6      0.07 2899  6.781286550
7      0.08 1733  4.053801170
8      0.09  951  2.224561404
9       0.1  443  1.036257310
10     0.11  192  0.449122807
hollyjolly
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0 Answers0