Basics of R

CIA Factbook Data

Revisit the CIA factbook dataset that you used for Assignment 1. (If you didn’t save it

or if your variable was not numeric, visit https://www.cia.gov/the-world-factbook/

references/guide-to-country-comparisons/ and choose a variable to get a csv. dataset

again). Import the dataset into R. Please answer the following questions with R and copy

the commands that you use for answering each question.

1. (.5 pt) Is the variable of interest correctly read as a numeric object? (if not, contact

the instructor for help)

2. (.5 pt) What are the average value of that variable?

3. (.5 pt) Does that average value happen to be the actual value of any country?

4. (.5 pt) How many countries are there whose value is below the average?

5. (.5 pt) Which country has the lowest value?

6. (.5 pt) Which country is ranked 10th, 30th, and 50th respectively?

7. (1 pt) Which country ranks higher in the variable that you choose, Namibia or

Botswana (the data might be missing in your dataset, but at least you need to

write down the R command that you use for inquiry)?

Presidential Approval Basics

Revisit the 538 polling dataset that you used for Assignment 1. Import the dataset into

R. Please answer the following questions with R and copy the commands that you

use for answering each question.

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1. (.5 pt) Is the dataset properly read in? How many observations and variables are

in the dataset?

2. (.5 pt) What are the dierent values of population?

3. (1 pt) What is the average approval for polls of each population? Does there

appear to be much of a dierence? (Hint: Create and save a subset of the data for

each methodology using indexing, subsetting, or ltering and nd the mean of that

new dataset.)

Presidential Approval Advanced

Use the same 538 dataset to address the following questions. Again, copy the commands that you use. When asked for the correlation between two variables, use the

function cor( x , y ) for the specic x and y that you want to compare. Make sure to use

the form `dataset$variable’ to indicate a variable that exists within a dataset.

1. (.5 pt) Using approve and disapprove, create a new variable in the dataset measuring

the dierence of approve to disapprove (subtract the variables). Using this new

variable, create a second new variable by taking the opposite (*-1). What is the

correlation between these two newly created variables?

2. (.5 pt) Using approve and disapprove, create a new variable in the dataset measuring

the ratio of approve to disapprove (divide the variables). Using this new variable,

create a second new variable by taking the inverse (∧-1). What is the correlation

between these two newly created variables?

3. (1 pt) What was the approve-disapprove ratio and dierence (two variables you just

created) for the polls that had the largest and smallest sample size?

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