Best Supplementary Texts for Casella and Berger are "Introduction to Probability" (first half) and "The Simple and Infinite Joy of Mathematical Statistics" (second half)

Making this post to help current and future grad students. I'd also to help departments choose good supplementary books for non-pure statistics programs, like biostatistics, economics, psychometrics, etc. I'm working through the tail end of a first year graduate mathematical statistics sequence. I only had an intro probability course using "Mathematical Statistics with Applications" by Wackerly beyond the typical math courses in engineering BS programs. Neither is as rigorous as "Statistical Inference", but they're close. I've found "Statistical Inference" clearer …

berger books current datascience economics etc future good introduction making probability psychometrics simple statistics students through