These are the libraries that over the years I have found useful repeatedly at work

Text processing

  • tm : for text analysis
  • quanteda : text processing

Data modeling

  • topicmodels : for LDA topic model
  • caret: for various data preprocessing functions, regression and classification
  • ROCR : model tuning and analysis
  • e1071 : building models

Time series

  • zoo :time series objects
  • xts : times series data manipulation
  • quantmod : financial charting and analysis

Workflow

  • devtools : for building and managing packages
  • testthat : for testing
  • roxygen2 : for package documentation

Others

  • RSQLite : use sqlite for quick database setup and queries
  • RJSONIO : json