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Date	Title	Categories
November 20, 2025 at 10:28 PM	Week 12 FAQs Can we make interactive maps with R? Why do we use an empty `ggplot()` call for these functions? What’s the difference between a tibble and a tribble? How many decimal points should I use when I’m working with latitude and longitude? Can I use `geom_label_repel()` with maps? I tried using `nudge_x` to move a label on the map and it didn’t move—why? Can I use a heatmap on a map? I tried to make a map and countries are missing—why? I tried to make a map of just Europe and it includes more than just Europe? Can we do geographic calculations with {sf}? Like, can we replace ArcGIS with R and {sf}? Saving data that takes a long time to make	FAQs
November 12, 2025 at 12:53 PM	Grades, zeroes, and ✓−s in the gradebook	course details
November 12, 2025 at 11:06 AM	Mini project 1 feedback Warnings and messages Raw LLM output Figure in the document doesn’t match the standalone image Sorting and ordering Unbalanced facets Overlapping text Commas Omit time-based axis titles Remove redundant legends Format code more consistently	FAQs feedback
November 11, 2025 at 12:10 PM	Week 11 FAQs How do I update my site if I make changes? Can we make our own websites to display our work and our projects? Can I customize the URL for my site? Like www.myname.com? Do people use Plotly and Quarto dashboards and websites in the real world? My plot didn’t translate perfectly to ggplotly—why? How did you get the two value text boxes to stack on top of each other in the bottom row? When should we use a dashboard vs. a full Shiny app? But I don’t want to learn a whole other language with OJS to show in-browser interactive graphs—is there a way to use R in the browser without Shiny? I rendered my file / dashboard but it didn’t appear in the Viewer panel—why not? Do people use viridis palettes in real life? I’m bored with ggplot’s default colors and/or viridis—how can I use other color palettes?	FAQs
November 5, 2025 at 11:42 AM	Week 10 FAQs How do I include a separate image in my document? When should we add annotations and text in R vs. in a separate program? Do people really do this two-step process of using R and then using Illustrator? Why can’t we use Canva for this? The Urban Institute style guide said to use 6.25 inches or 720 pixels, but in Illustrator/Affinity/Inkscape, it translated 6.25 inches to 450 points—why?	FAQs
November 2, 2025 at 4:19 PM	LLMs are bad and dangerous for learning how to code in this class	advice
October 31, 2025 at 11:59 AM	Week 9 FAQs There are so many ggplot-specific R packages—how can we remember them or find them all? What’s the difference between `labs()` and `annotate(geom = "text")`? What’s the difference between `geom_text()` and `annotate(geom = "text")`? How do I know which aesthetics geoms need to use? It’s annoying to have to specify annotation positions using the values of the x/y axis scales. Is there a way to say instead? What’s the difference between `geom_text()` and `geom_label()`? What does `update_geom_defaults()` do? How do annotations work with facets? The importance of layer order Seeds—why?	FAQs
October 21, 2025 at 11:58 AM	Week 8 FAQs We keep seeing violin plots, but they’re still confusing (and ugly and weird). Why are they a thing? Using `paste0()` to build complex text is annoying! Is there a better way? Why did my slopegraph labels repeat on both sides? The guide lines in the slopegraph look like real lines of data! Is there a way to fix that? I have numbers like 20000 and want them formatted with commas like 20,000. Can I do that automatically? Are geofacet plots used in real life? How can I get month and weekday names or abbreviations for dates? Can I get these automatic month and day names in non-English languages?	FAQs
October 14, 2025 at 9:13 PM	Week 7 FAQs Is there some place I can find R packages? There are so many! When is it better to use `augment()` vs. `marginaleffects::predictions()`? I’ve used `summary()` in the past to look at model objects, but you recommend using `tidy()`. Why? I tried to render my document and got an error about duplicate chunk labels. Why? I tried calculating something with `sum()` or `cor()` and R gave me NA instead of a number. Why? Should I always just use `na.rm = TRUE` then? What about missing data with regression? What does R do then? I want my bars to be sorted in my plot. How can I control their order? Are there other legitimate cases for using dual y-axes?	FAQs
October 8, 2025 at 8:04 PM	Week 6 FAQs Am I telling R what to do with my code, or is it telling me what to do? Who’s in charge? Why isn’t it listening?! Do I really need to make fancy custom themes for every plot? Aren’t `theme_bw()` or `theme_gray()` just fine? I have numbers like 20000 and want them formatted with commas like 20,000. Can I do that automatically? I tried using {gghalves} and `geom_half_point()` but I got an error? My histogram bars are too wide / too narrow / not visible. How do I fix that? Does it matter which order we put the different layers in?	FAQs
September 30, 2025 at 8:37 AM	Week 5 FAQs This is too much code—Tableau can do all this, so why can’t we use that? Why should I use `ggsave()` instead of just rendering a Quarto document? I made a bunch of changes to my plot with `theme()` but when I used `ggsave()`, none of them actually saved. Why? Does the order of theme things matter? I made changes with `theme()` and then wiped them out with `theme_minimal()`? If I want to use the same theme for all the plots in my document, do I need to reuse all that code all the time? Why would we want to use `rel(1.4)` instead of actual numbers when sizing things? Why can’t I change title text with `theme()`? I’m using macOS and couldn’t render as PDF when using a custom font—how do I fix that? In chapter 22, Wilke talks about tables—is there a way to make pretty tables with R? Double encoding and excessive legends Legends are cool, but I’ve read that directly labeling things can be better. Is there a way to label things without a legend? Can we fill with a pattern instead of colors?	FAQs
September 22, 2025 at 4:40 PM	Week 4 FAQs I can’t remember everything I need to type / I can’t memorize all the code / I had to look stuff up on the internet / Why didn’t you cover this specific thing? It seems weird that we can randomly jitter points to accurately reveal relationships? I want my lollipop/bar chart to go sideways—how do I do that? Why does R keep yelling at me with warnings and messages? Why do I keep getting messages like `summarise() has grouped output by 'BLAH'` when using `group_by()` and `summarize()`? When do we use `summarize()` vs. `mutate()` with `group_by()`? How can I hide warnings and messages? Why did we need to group a second time when calculating the proportions for the heatmap? How can I add a line break to the text in my plot? How can I control the dimensions of my figures?	FAQs
September 19, 2025 at 7:54 PM	Week 3 FAQs What’s the difference between the `\|>` and `%>%` pipes? Why do we sometimes combine code with `+` and sometimes with `\|>`? Why doesn’t `group_by(species)` work but `group_by(Species)` does? Why does `aes()` sometimes appear in `ggplot()` and sometimes in `geom_WHATEVER()`? Installing vs. using packages Why are my axis labels all crowded and on top of each other? How do I fix that? Why isn’t the example code using `data = whatever` and `mapping = aes()` in `ggplot()` anymore? Do we not have to use argument names? What’s the difference between `geom_bar()` and `geom_col()`? What’s the difference between `read_csv()` vs. `read.csv()`? What’s the difference between `facet_grid()` and `facet_wrap()`? Why do I sometimes see `facet_wrap(vars(blah))` and sometimes `facet_wrap(~ blah)`? What’s the difference between the `fill` and `color` aesthetics? Why did we need to group and summarize before making the Lord of the Rings plots? I didn’t and the plot still worked	FAQs
September 9, 2025 at 11:03 AM	Week 2 FAQs Why do you use ✓s for grades? Why does `#` mean both headings and code comments? I will never do anything with graphic design—why did we have to learn these principles? How does CRAP relate to other things like the Gestalt Principles? Does something need to have all four elements to be well designed? Or can it have contrast and not alignment? Are the CRAP principles hard-and-fast rules? Will following CRAP lead to the same final designs? Does CRAP only work for single-page things like graphs and posters? Or does it work for reports and books? I noticed Illustrator isn’t free for GSU students anymore. Are there other graphics editors? Is there a way to check that my color palettes are accessible if I’m not using a premade one? I wanted to try other fonts, but I can only see a few in Microsoft Word? Where can I find fonts to use?	FAQs
September 6, 2025 at 3:58 PM	Copy, paste, and tweak	advice
September 6, 2025 at 2:58 PM	Making cleaner, nicer Quarto documents Render often Check for broken code chunks Check that your text looks okay Don’t install packages in your document Clean up warnings and messages Global chunk options Fancy document settings Chunk names	advice
September 6, 2025 at 2:00 PM	Week 1 tips and FAQs What’s the difference between Source and Visual mode in the editor window? What’s the difference between R Markdown and Quarto? Why don’t I have options to render to PDF (or Word or HTML)? Rendered document format for iCollege What is this thing that we can render to? How does `group_by()` work? Why did we have to group by `island` and not `body_mass` and `island`? How do we know which type of graph to use for different types of data? Do you have any tips for remembering all the different functions we’re learning? There are so many!	FAQs
August 25, 2025 at 3:14 PM	How to ask for help Don’t suffer in silence! Use Discord in public Help us help you High resolution questions Unanswered questions Discord question etiquette Calendly + Webex appointments	advice
August 25, 2025 at 3:12 PM	First day of class!	getting started
August 21, 2025 at 2:44 PM	Building community on Discord Class community Online community	advice
August 21, 2025 at 1:18 PM	Announcements and updates	getting started
August 21, 2025 at 12:42 AM	Important R stuff	getting started
August 20, 2025 at 1:08 PM	Welcome to class!	getting started

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