introduction to r programming for data science coursera answers week 1
Practice Quiz
1. Which of the following are examples of predictive analysis? Select two answers.
- Pandemic trends prediction.
- Understanding human languages.
- Returning a summary of descriptive statistics for data.
- Dashboards.
2. Which of the following statements about numeric and integer values are true? Select three values.
- A numeric value can be converted to an integer.
- An integer can be converted to a numeric value.
- The converted value of a numeric to an integer is always equal to the original numeric value.
- The converted value of an integer to a numeric is always equal to the original integer value.
3. What is the result of the R expression 4 + 3 * 25?
- 79
- 175
- 74
- 103
4. Which R function saves a workspace to a .RData file?
- save.data()
- save.workspace()
- save.image()
- save.file()
5. In RStudio, which of the following statements about writing code in the File Editor and the Console are true? Select two answers.
- You write code, usually for multiple lines of code, in the File Editor and execute them in batch mode.
- Code in the File Editor executes immediately as you type it so you can see the results quickly.
- Only files containing R code can be edited in the File Editor
- You write code in the Console when you want to try out R commands or to run a few lines of code.
6. Complete the statement: A Jupyter Notebook is made up of a series of _______________ that you can use to write, run, and interact with your code.
- Files
- Cells
- Objects
- Workspaces
Graded Quiz
7. R can perform several forms of statistical computation. What is an example of hypothesis testing?
- Testing if the mean values of two groups are statistically different.
- Inferring an unknown mean value of a population from its samples.
- Obtaining a representative subset of data.
- Compute and visualize a correlation matrix among four different variables to see if they are correlated.
8. Which of the following data type conversions may be not allowed in R?
- integer (like 1L or 2L) to numeric
- numeric (like 1 or 2) to integer
- logical (like TRUE or FALSE) to numeric
- character (like `1`, `A`, or `test`) to numeric
9. What is the result of the R expression 100 * (5 – 3)?
- 200
- 497
- 503
- 500
10. After you write code in an R script file or the R Console, what component of the R environment parses the code into objects in memory?
- R Workspace
- R Interpreter
- R data files
- R variables, functions, and datasets
11. Which features of RStudio help facilitate code writing? Select two answers.
- File Explorer
- Code auto completion
- Syntax highlighting
- Workspace visualization
12. True or False: Execution order does not matter when executing cells in a Jupyter notebook
- True
- False