Example code illustrating different methods of model selection

• The following R program modelselect.r is a simplified version of the code used in the lecture note On Model Selection in Cosmology by M. Kerscher and J. Weller (2019).
• To run this example you need the Union 2.1 data file SCPUnion2.1_mu_vs_z.txt from the Supernova Cosmology Project.
• You also need the R packages bbmle and mcmc.
• Only the coding for the ΛCDM model is included in this example. The size of the MCMC chain and the length of the bootstrap sampling is reduced. Therefore the code runs on a current (2019) desktop computer in about a minute. For serious application you should increase these values significantly