Knowledge Quiz: Basic Commands

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Which of the following commands represents the recommended way to assign the value 7 to the object y?

y |> 7y + 77 -> yy <- 77 <- y

Although there are three valid assignment operators: <-, ->, =, only the left-facing arrow is recommended by most style guides.

• This is a misuse of the native R pipe operator.
• This command adds the value of y to the value of 7 and prints the result.
• This is technically valid assignment, but putting the variable on the right-hand side of the assignment operator is not recommended style.
• Correct
• This isn’t legal R code. This command attempts to assign the value y to the variable 7, but variable names can’t begin with numbers.

What value will the following R code produce?

(2 + 4) * 3 - 8

By applying the appropriate order of operations, we get 10.

Which of the following expressions will return TRUE?

"alice" == "bob" & "alice" == "alice"TRUE"alice" == "bob" | "alice" != "alice"TRUE & FALSE!TRUEFALSE

• FALSE: “alice” is not equal to “bob”
• TRUE: Trivially
• FALSE: “alice” is not equal to “bob”, and “alice” is equal to “alice”
• FALSE: Trivially
• FALSE: Trivial negation
• FALSE: Trivially