data analysis with r coursera week 1 quiz answers

Practice Quiz

1. Data analysis plays an important role in which of the following scenarios? Select 3 answers.

  • Predicting the future. 

  • Answering questions.

  • Finding data.
  • Discovering useful information.

2. Complete the sentence: In a dataset, a ___________________________ is also referred to as a variable, feature, or attribute.

  • Observation
  • Column
  • Row
  • Data frame

3. Which tidyverse package is used for data import and management?

  • dplyr
  • tidyr
  • readr
  • ggplot2

4. What is the next step must you perform after you download a dataset file from a URL?

  • Download the file using the download.file() function.
  • se the read_csv() function to read the dataset into a data frame.
  • Unzip the file using the untar() function.
  • Use the write_csv() function to read the dataset into a data frame

5. You are checking your data using the glimpse() function before beginning your analysis and determine that the data type of a variable called TimeStamp is in a character format. What should you do next?

  • Evaluate how you plan to use this variable in your data analysis.
  • Immediately change the character type to a date type.
  • Drop that column since it is too tricky to handle.
  • Nothing. R functions can handle dates and times in character format without modification.

Graded Quiz

6. What is the purpose of the Data Asset eXchange?

  • Provides data that is only useful for learning purposes.
  • Helps you exchange data with others.
  • Provides data that you can use for a small fee.
  • Provides data that you can explore to conduct data analysis.

7. In the Airline Performance dataset from the Asset Data eXchange, which of the following variables is a target for predicting on-time arrivals?

  • ArrDelay
  • CarrierDelay
  • Distance
  • SecurityDelay

8. What is the purpose of the pipe (%>%) operator?

  • Assigns a value to a variable.
  • Assigns a value to a global variable.
  • Combines multiple functions into a single operation.
  • Combines two functions into a single operation.

9. Which function can you use to read a text file that uses the “%” character as a delimiter?

  • read_csv()
  • read_delim()
  • read_tsv()
  • read_any()

10. What is the main similarity between the summarize() and group_by() functions?

  • Both return a statistical summary of the data.
  • Both group data by the specified variables.
  • Both compute summary statistics.
  • There is no similarity between the summarize() and group_by() functions.

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