Homework 03 is ready for grading

[suminwei2772]

1. README.md for hw03

2. gapminder_dplyr_ggplot2_exploration.md

[hannahdxz]

Hi Lisa! Thank you for inviting me on your GitHub. Here's my peer review for Homework 03. Hopefully you find these comments helpful!

Your README file in your HW repository was easy to navigate with the links for each homework session. The README file for HW03 was also very easy to navigate with links. The HW03 README was very informative, and concise.

Great exploration of the Gapminder data. I liked how you organized your analysis with section headers, which made your code very clear and easy to follow. You demonstrated a good knowledge of coding syntax. Your use of dplyr() and ggplot2() is quite diverse, and you used kable() functions to display your data. For each table, there is a relevant figure for visualization which was very helpful and informative to help understand the table. You explained both the code and the plots thoroughly so it is easy to understand how you got those plots and what does each plot means.

You tackled 5 tasks, which exceeded the requirements in number of tasks! I think you did a really great job exploring the data in the section Task 1: Compute trimmed mean (and untrimmed mean) of life expectancy, You had two trimmed means and you plot them on the same plot with the untrimmed mean, that ggplot was very impressive and informative!

One suggestion might be in the Task 3: Look at spread of gdp per capita for each continent, you plotted the distribution of the continents with the greatest and lowest spreads. I would suggest to use box plot in this section, side by side box plot would give a very clear comparison between these two continents.

Overall, thank you for your great work and I hope you enjoy this class!

[estennw]

Hi Lisa,

This is a great piece of work, and you've made some beautiful plots. You exceed the number of tasks required, while delivering high performance on each task nevertheless.

Code Your code is really nice, and well structured. I want to advice you to add comments to your code, however it's so easy to read that it's really not necessary to add any comments. You use dplyr really efficient, and you don't use any more code than needed. Perfect!

Tables It's always nice to see some well crafted kable tables. The tables look nice, and your use of input variables like align and col.names gives the tables a finished look. Tips:

• I guess this is not so relevant for this homework but still, a tip. In task 5, you produced a really tall table, and the reason for being so tall is that you had two variables, continent and year. I could have been nice to have for example continent as row and year as column. This can be achieved with:

gapminder %>% 
  filter(lifeExp < 59.47444)  %>% 
    group_by(continent,year) %>% 
      summarize(distinct_countries=n_distinct(country)) %>% 
        spread(key=year, value=distinct_countries) %>%
          knitr::kable(format="markdown",align=c(rep('c',times=7)), padding=2) 

which results in this

continent	1952	1957	1962	1967	1972	1977	1982	1987	1992	1997	2002	2007
Africa	52	52	51	50	50	49	43	39	38	39	41	40
Americas	19	15	13	10	8	7	5	2	1	1	1	NA
Asia	29	26	25	23	19	14	11	8	7	6	3	1
Europe	5	3	1	1	1	NA	NA	NA	NA	NA	NA	NA

Of course, it's not very pretty with the NA's but it's worth considering. This can also be done with the other tall table.

Figures Amazing, really nice looking, and so sparse that each figure is easily interpretable. I was especially impressed by the trimmed means plot. That plot tells you a lot about whether outliers are located above or below the median.

Impressive work, it was a nice read!

[pgonzaleze]

Hi @suminwei2772 , here are some comments about your work: At least three tasks: Yes
A table and figure for each task: Yes
Comments on tables/figures: Yes Reflections on Process: Yes Bonus (side-by-side layout, new table packages): Yes (side-by-side)

• You accomplished the requirements for this assignment,
• It would be nice to have a brief explanation of what you are planning to do, and after get some product, this will facilitate the readers the understanding of your work,
• The figures are ok for practice, just be careful to select the correct one, e.g. you selected the geom_histogram() with alpha, this overlap the colors and cause the change of them. In this case is not a big issue since you have two colors but could become a problem if there are three colors for instance.
• The indentation facilitate the reading but I don´t think is necessary to indent after the “+” character, anyway is just a style comment!
• I did not get the aim of the last task, but I liked the integration of functions!
• Well done!

Your marks will be distributed later, Regards,

Pedro G.