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**Data Management**: reading & writing data, date formats, and reshaping

- How to Input data into R
- How can I sort my data in R?
- How can I format a string containing a date into R “Date” object?
- How can I get a table of basic descriptive statistics for my variables?
- How can I subset a data set?
- How can I identify the first and last observations within a group in R?
- How does R handle missing values?
- How does R handle date values?
- How can I reshape my data in R?
- How can I “collapse” my data in R?
- How can I convert from person-level to person-period?

**R Interface**: basics and package management

- How can I see what data sets are available when I started R?
- The very basics of R
- How can I save my data and graphs in a different format?
- How can I manage R packages?
- How can I time my code?

**Graphics**: scatter plots, smooth lines, longitudinal visualization

- How can I overlay plots in a trellis graph?
- How can I make spaghetti plots?
- How can I visualize longitudinal data in ggplot2?
- How can I make individual growth curves in ggplot2?
- How can I explore different smooths in ggplot2?
- How can I do a scatterplot with regression line or any other lines?
- How can I change the angle of the value labels on my axes?
- How can I add features or dimensions to my bar plot?

**Statistics**: significance tests, and statistical models not covered under data analysis examples

- Choosing the Correct Analysis for Various Survey Designs
- How can I generate a variogram for spatial data in R?
- How can I generate a Venn diagram in R?
- How do I fit a variogram model to my spatial data in R using regression commands?
- How do I model a spatially autocorrelated outcome?
- How can I manage and plot social network data?
- How can I generate bootstrap statistics in R?
- How can I estimate the standard error of a transformed parameter in R using the delta method?
- How can I do post-hoc pairwise comparisons in R?
- How can I get Type III tests of fixed effects in R?
- How can I explain a continuous by continuous interaction?
- How can I perform seemingly unrelated regression in R?
- How can I test contrasts in R?
- How do I perform multiple imputation using predictive mean matching in R?

**Random coefficient models**

- Random coefficient poisson models
- Multivariate random coefficient model
- How can I perform mediation with multilevel data? (Method 2)

**Other**