Homework 03 is ready for grading

[sepkamal]

Please see here for my hw3! https://github.com/sepkamal/STAT545-hw-Kamal-Sepehr/blob/master/Hw03/hw03-dplyr-manipulation.md

Thanks

[Jennica416]

Hey @sepkamal,

I thought your document was really well organized and appreciated the notes within the code that made it easier to understand what you were doing. One overall suggestion is to use the spell check button within RStudio as a final step in preparing your assignments as there were a fair number of typos throughout the document. Lastly, I think your explanations for the graphs are a good start and appreciate that they are there. That said, I would recommend adding more details around why you selected the plot you did and/or another sentence or two about the output in the future to make interpretations more clear.

Q1 Min + Max GDP per Capita:

• Great use of piping
• Using an error bar graph was an interesting way to see the difference between min and max
• GDP per capita, in my opinion, is associated with year and therefore you might want to think about grouping by continent and year then exploring min/max over time. I think this would allow for more meaningful interpretations.

Q2 GDP per Capita Spread

• Again, great use of piping
• I think you meant to display the table "my_gap_means" rather than the table from #1 (i.e. "min_max_gdp") as the one shown does not much information about spread.
• I really liked the v-line as mean. For the future, you might think of adding another vertical line (another colour) that shows median. With so many outliers, knowing both mean and medium helps one better understand the spread.
• Boxplot to show outliers was really helpful. Again, I wonder if this should have been filtered to show a single year to make it a more meaningful interpretation.

Q3 Abundance of Low Life Expectancy

• great use of counting true to calculate the number of countries with low life expectancy
• great piping

Q4 Top 10 /Bottom 10 Change in Life Expectancy

• this was an interesting question to explore
• I liked that you coloured the bar based on continent as it add another layer of understanding in the visual
• In the future, you may want to think about ordering the bars by size rather than alphabetically to make it easier to interpret.

Overall, great job! I also dislike tables so am glad to know I am not the only one :)

Best, Jennica

[KateJohnson]

Hi @sepkamal

• Your markdown file is very well organized and easy to read.

Task 1: Good table. Your ggplots displayed the data. As you mentioned, it would have been nice if you had min and max GDP on the same plot (I did it by reshaping the data so there were two rows for each continent with the min and max in each row). Also, you could use xlab() or ylab() to rename the axis. I really liked the GDP range ggplot, it shows the data well, but I didn’t see where you transformed GDP to the log scale (but I might have just missed it).

Task 2: This table is the same as in Task 1. I think you just used the wrong data frame accidentally. Also, you can rename the table columns using col.names() I really liked your GDP distribution per continent ggplot. It shows the data in a really interesting way.

Task 3: Really good use of dplyr! Great idea to use the quintile function. The ggplot compliments the table nicely.

Overall, check plus.

[derekcho]

Hi @sepkamal! Here are some comments about your hw03:

• You don’t need to make a copy of gapminder. It won’t change because you are not assigning another object to gapminder, you assign it to something else anyways. For example, you can just do this: min_max_gdp = gapminder %>% rest_of_code_here
• I would advise against doing a barplot like the way you have done to show min and max gdp where you split them across two graphs (the scales are not the same and it is hard to see the range). You could combine them into the same graph with barplots instead. However, your third plot is much better where it shows the ranges in log scale.
• If you have code that you do not use, you should just remove it rather than commenting it out (this should also be visually appealing!)
• In general, your tables are all very well done! They are easy to read, informative and visually appealing since you were able to knit them with kable. Good work!
• You do not need to display the entire table if the table has several rows, showing just the head is usually fine!
• There seems to be an issue with text and plot alignment in your report. Some lines of text start at the end of plot (sharing the same line). Perhaps you can add another empty line in between your plots and explanations.
• Solid work overall, you provided good explanations of what you were doing in each task and you were able to complete 4 tasks successfully. Your report is generally well organized and split up into appropriate sections. Nice job!

Note: your mark (check minus, check, check plus) will be distributed later.