Please complete before the next class.

Make sure that you’ve completed all previous HW first.

## Handedness

Note: *I fixed a bug in the initial version of the survey** that made it impossible to fill out (h/t Jessica). We’ve only had 9 responses as of 8:30 Wednesday, so fill it out if you get a chance.

Fill out the survey here.

## Loading Data

As I mentioned in class, I’ve had excellent results with RStudio Cloud so far. I encourage you to switch if you run into problems. So far, it offers a much shallower learning curve by resolving two unimportant technical difficulties (installation and working directories, if you’re curious). The only downsides I’ve found are that you must be connected to the web and it’s slightly slower to load.

Read and review your notes, my notes, and my slides over the basics of loading data into R. Answer the review questions thoughout the document. Remember to practice!

• I also created a public project in RStudio Cloud that you can look at and/or copy to help you with the review exercises. Log in first (you can use the GitHub account you created earlier), then click here. Under the Files tab in the lower-right panel, click load-data.R to open my script. It makes a cool plot, too.
• Like the previous assignment, this is a tedious assignment–you’ll need to work carefully. I suggesting spreading the exercise over several different sessions to give you time to digest the ideas. Don’t rush it. The previous assignment covered many simple ideas–this assignment covers a fewer, but more complex ideas.
• I’ve found that working in groups helps when you are stuck.
• I try to write exam questions that students who can do the review exercises will answer correctly and quickly (and that others will answer incorrectly and/or slowly).
• When you can’t get your code to work, it’s usually just a missing parenthesis or quotation mark. It’s not that you’re making a huge mistake. Huamns can sitll mkae snese wehn tehre are tpyos, but not computers! Check your code for typos carefully. Run your script one line at a time, from top to bottom, to find mistakes. As examples, most mistakes are like the following:
b <- c("Male", "Female)  # missing the second " after "Female"
exp(23  # forgot to close a parentheses
log(10 base = 2)  # missing comma between arguments

a <- c(1, 2, 3)
mean(A)  # R is case-sensitive--there's an object "a", but no object "A"
mena(a)  # misspelled function name
Mean(a)  # R is case-senstive

Carlisle Rainey