hw04 ready for grading

[jmurthy12]

Hello,

My Homework 04 is ready to be reviewed and here is the Link : https://github.com/jmurthy12/STAT545-hw-murthy-janani/tree/master/hw04

SHA: 1eb9767

Gapminder exploration .md file: https://github.com/jmurthy12/STAT545-hw-murthy-janani/blob/master/hw04/Homework04_dataReshaping.md

@vincenzocoia @gvdr @ksedivyhaley @JoeyBernhardt @mynamedaike @pgonzaleze @derekcho

Thanks, Janani.

[xinyaofan]

Hi, I am happy to review your work and I think you did a great job!

Some good things:

• You gave a clear header of each part in your homework, so your homework is in a tidy format. You completed 4 prompts which beyonds the requirements of the homework.
• You explored function gather() spread(), dcast() in detail, and draw some plots by taking the advantage of the reshaped data, that's really good ! So, it's really a good cheatsheet for 'tidyr'.

Some improvements:

• In your cheatsheet of 'join', perhaps you could change the order of your datasets and use these inner_join, left_join() etc again to see what happens. I think you could learn how the order of dataset influence the result of each function by doing this.
• Actually, I am a confused about the plot in activity 4, the code seems a little long. It seems that it becomes difficult to draw a plot after reshaping the table, could you think another type of plot which could take the advantages of such table? Just try~

Overall, you did a nice work, Check Plus！

[shadowforti]

Hello

Well done.

• I like your cheat sheets which are very concise and straightforward.
• Dcast function is included, which I haven't tried
• Nice plot with clear titles, legend, and colors
• Well demonstration of all the functions
• Each step is explained and clearly described
• More activities have been done than required

Suggestions:

• Some tables could be better presented with knitr or other applications.
• Some headers are bold but some are not

Overall, the homework is great. Check-plus

Thanks

Jian

[ksedivyhaley]

Reshaping activity: Yes (several, but see comments) Join activity: Yes Reflect on process: Yes Bonus (merge/match): No

Comments:

• Interesting how dcast() summarizes when it sees two songs in the same year, but spread() fails.
• You forgot a + in your first ggplot, so your title is missing.
• No plot for activity 3, but OK because Activity 2 covered that aspect.
• For activity 4, you're supposed to get a table showing the max and min life expectancy (two columns per continent), not the mean. This is a bit trickier to do – intentionally!
• It is easier to see how joins work if you use a smaller dataset – the reader can't really see the results for some of these because you can't fully display gapminder.

Your mark will be distributed later. If you would like more feedback, please feel free to message me on slack.