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table of contents
Packages & Functions Reference
This table consolidates the packages and commands used throughout the book, what each command does, and where it is first introduced.
| Package | Command | What it does | First introduced |
|---|---|---|---|
| base R | <- | Assigns values to objects for later use. | Introduction to R |
| base R | c() | Combines multiple values into a single vector. | Introduction to R |
| base R | : | Creates integer sequences (e.g., 1:10). | Introduction to R |
| base R | [] | Indexes and subsets elements from vectors or data frames. | Introduction to R |
| base R | $ | Accesses or creates columns within a data frame. | Introduction to R |
| base R | sqrt() | Computes square roots. | Introduction to R |
| base R | log() / log10() | Computes natural and base-10 logarithms. | Introduction to R |
| base R | round() | Rounds numeric values to a specified number of digits. | Introduction to R |
| base R | class() | Identifies the data type (class) of an object. | Introduction to R |
| base R | length() | Returns the number of elements in a vector. | Introduction to R |
| base R | factor() | Converts character data into categorical (factor) variables. | Introduction to R |
| base R | levels() | Displays the levels associated with a factor. | Introduction to R |
| base R | data.frame() | Combines vectors into a tabular data structure. | Introduction to R |
| base R | head() / tail() | Displays the first or last rows of a dataset. | Introduction to R |
| base R | str() | Displays the internal structure and data types of a dataset. | Introduction to R |
| base R | summary() | Produces descriptive summaries of variables or model results. | Introduction to R |
| base R | table() | Creates frequency tables for categorical data. | Introduction to R |
| base R | nrow() / ncol() | Returns the number of rows or columns in a dataset. | Introduction to R |
| base R | colnames() | Displays or modifies column names of a data frame. | Introduction to R |
| base R | read.csv() | Imports CSV files into R as data frames. | Introduction to R |
| base R | getwd() / setwd() | Gets or sets the current working directory. | Introduction to R |
| base R | install.packages() | Installs packages from CRAN. | Introduction to R |
| base R | library() | Loads an installed package into the current R session. | Introduction to R |
| base R | ?function_name | Accesses built-in help documentation for a function. | Introduction to R |
| magrittr | %>% | Passes the result of one operation into the next. | Introduction to tidyverse |
| dplyr | select() | Chooses specific columns from a dataset. | Introduction to tidyverse |
| dplyr | filter() | Keeps rows that meet logical conditions. | Introduction to tidyverse |
| dplyr | arrange() | Orders rows based on column values. | Introduction to tidyverse |
| dplyr | mutate() | Creates or modifies columns. | Introduction to tidyverse |
| dplyr | rename() | Renames columns using new_name = old_name. | Introduction to tidyverse |
| dplyr | distinct() | Returns unique rows or value combinations. | Introduction to tidyverse |
| dplyr | if_else() | Creates values based on a binary condition. | Introduction to tidyverse |
| dplyr | case_when() | Applies multiple conditional rules. | Introduction to tidyverse |
| base R | is.na() | Identifies missing (NA) values. | Introduction to tidyverse |
| tidyr | drop_na() | Removes rows containing missing values. | Introduction to tidyverse |
| dplyr | count() | Counts observations by group. | Introduction to tidyverse |
| dplyr | group_by() | Groups data for grouped operations. | Introduction to tidyverse |
| dplyr | summarise() | Computes summary statistics for groups. | Introduction to tidyverse |
| dplyr | n() | Returns group size within summarise(). | Introduction to tidyverse |
| base R | sessionInfo() | Displays information about the current R session, including loaded packages. | Introduction to tidyverse |
| dplyr | inner_join() | Performs a SQL-style inner join, keeping only rows that match in both datasets. | Comparing Two Groups |
| tidyr | pivot_longer() | Converts data from wide format to long format. | Comparing Two Groups |
| tidyr | pivot_wider() | Converts data from long format back to wide format. | Comparing Two Groups |
| base R | rbind() | Combines multiple data frames by binding rows together. | Comparing Two Groups |
| base R | merge() | Joins two data frames together based on a shared key variable. | Comparing Two Groups |
| base R | mean() | Calculates the average of numeric values. | Comparing Two Groups |
| stats | t.test() | Tests whether two group means differ significantly. | Comparing Two Groups |
| stats | cor() | Computes Pearson correlation coefficients. | Correlation Analysis |
| stats | cor.test() | Computes and tests correlations. | Correlation Analysis |
| base R | pairs() | Creates a scatterplot matrix. | Correlation Analysis |
| GGally | ggpairs() | Enhanced scatterplot matrix with correlations. | Correlation Analysis |
| ppcor | pcor.test() | Computes partial correlations. | Correlation Analysis |
| base R | ifelse() | Recodes variables conditionally. | Correlation Analysis |
| base R | set.seed() | Ensures reproducibility when generating random data. | Comparing Multiple Means |
| stats | rnorm() | Generates random values from a normal distribution. | Comparing Multiple Means |
| stats | aov() | Fits ANOVA models. | Comparing Multiple Means |
| supernova | supernova() | Displays ANOVA results in structured tables. | Comparing Multiple Means |
| stats | TukeyHSD() | Performs post-hoc pairwise comparisons. | Comparing Multiple Means |
| base R | plot() | Visualizes post-hoc comparison results. | Comparing Multiple Means |
| AICcmodavg | aictab() | Compares models using AIC. | Comparing Multiple Means |
| base R | xtabs() | Constructs contingency tables using a formula interface. | Analyzing Categorical Data |
| janitor | tabyl() | Creates clean contingency tables. | Analyzing Categorical Data |
| janitor | adorn_percentages() | Converts counts to percentages. | Analyzing Categorical Data |
| janitor | adorn_ns() | Displays counts and percentages together. | Analyzing Categorical Data |
| janitor | clean_names() | Cleans names of an object. | Correlations |
| stats | chisq.test() | Performs Chi-Square tests of independence. | Analyzing Categorical Data |
| gmodels | CrossTable() | Detailed cross-tabulations. | Analyzing Categorical Data |
| pheatmap | pheatmap() | Heatmap visualization of residuals or contributions. | Analyzing Categorical Data |
| rcompanion | cramerV() | Measures association strength between categorical variables. | Analyzing Categorical Data |
| stats | lm() | Fits linear regression models. | Linear Regression |
| broom | tidy() | Tidies model coefficients. | Linear Regression |
| broom | glance() | Extracts model-level statistics. | Linear Regression |
| lmtest | bptest() | Tests heteroscedasticity. | Linear Regression |
| stats | AIC() | Compares regression models. | Linear Regression |
| stats | step() | Performs stepwise model selection. | Linear Regression |
| stats | glm() | Fits generalized linear models, including logistic regression (binomial family). | Logistic Regression |
| base R | exp() | Converts log-odds to odds ratios. | Logistic Regression |
| caTools | sample.split() | Splits data into training/testing sets. | Logistic Regression |
| caret | confusionMatrix() | Evaluates classification performance. | Logistic Regression |
| pscl | pR2() | Computes pseudo R² values. | Logistic Regression |
| caret | varImp() | Assesses predictor importance. | Logistic Regression |
| car | vif() | Detects multicollinearity. | Logistic Regression |
| pROC | roc() | Builds ROC curves. | Logistic Regression |
| pROC | auc() | Computes area under the ROC curve (AUC). | Logistic Regression |
| knitr | knitr::opts_chunk$set() | Sets global chunk options in R Markdown. | Reproducible Reporting |
| knitr | kable() | Creates formatted tables for reports. | Reproducible Reporting |
| nycOpenData | nyc311() | Downloads NYC 311 Service Request data from NYC Open Data. | Reproducible Reporting |
citation("base")
#> To cite R in publications use:
#>
#> R Core Team (2025). _R: A Language and Environment
#> for Statistical Computing_. R Foundation for
#> Statistical Computing, Vienna, Austria.
#> <https://www.R-project.org/>.
#>
#> A BibTeX entry for LaTeX users is
#>
#> @Manual{,
#> title = {R: A Language and Environment for Statistical Computing},
#> author = {{R Core Team}},
#> organization = {R Foundation for Statistical Computing},
#> address = {Vienna, Austria},
#> year = {2025},
#> url = {https://www.R-project.org/},
#> }
#>
#> We have invested a lot of time and effort in creating
#> R, please cite it when using it for data analysis.
#> See also 'citation("pkgname")' for citing R packages.
citation("ggplot2")
#> To cite ggplot2 in publications, please use
#>
#> H. Wickham. ggplot2: Elegant Graphics for Data
#> Analysis. Springer-Verlag New York, 2016.
#>
#> A BibTeX entry for LaTeX users is
#>
#> @Book{,
#> author = {Hadley Wickham},
#> title = {ggplot2: Elegant Graphics for Data Analysis},
#> publisher = {Springer-Verlag New York},
#> year = {2016},
#> isbn = {978-3-319-24277-4},
#> url = {https://ggplot2.tidyverse.org},
#> }
citation("dplyr")
#> To cite package 'dplyr' in publications use:
#>
#> Wickham H, François R, Henry L, Müller K, Vaughan D
#> (2023). _dplyr: A Grammar of Data Manipulation_.
#> doi:10.32614/CRAN.package.dplyr
#> <https://doi.org/10.32614/CRAN.package.dplyr>, R
#> package version 1.1.4,
#> <https://CRAN.R-project.org/package=dplyr>.
#>
#> A BibTeX entry for LaTeX users is
#>
#> @Manual{,
#> title = {dplyr: A Grammar of Data Manipulation},
#> author = {Hadley Wickham and Romain François and Lionel Henry and Kirill Müller and Davis Vaughan},
#> year = {2023},
#> note = {R package version 1.1.4},
#> url = {https://CRAN.R-project.org/package=dplyr},
#> doi = {10.32614/CRAN.package.dplyr},
#> }
citation("tidyr")
#> To cite package 'tidyr' in publications use:
#>
#> Wickham H, Vaughan D, Girlich M (2024). _tidyr:
#> Tidy Messy Data_. doi:10.32614/CRAN.package.tidyr
#> <https://doi.org/10.32614/CRAN.package.tidyr>, R
#> package version 1.3.1,
#> <https://CRAN.R-project.org/package=tidyr>.
#>
#> A BibTeX entry for LaTeX users is
#>
#> @Manual{,
#> title = {tidyr: Tidy Messy Data},
#> author = {Hadley Wickham and Davis Vaughan and Maximilian Girlich},
#> year = {2024},
#> note = {R package version 1.3.1},
#> url = {https://CRAN.R-project.org/package=tidyr},
#> doi = {10.32614/CRAN.package.tidyr},
#> }Annotate
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