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X <- list(a=1,b=2,c=3) creates____.

A) A vector containing the elements 1, 2, and 3.
B) A data frame with columns "a," "b," and "c."
C) A named list with elements "a," "b," and "c."
D) A matrix with named rows and columns.

User Discolor
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Final answer:

In the R programming language, using the command x <- list(a=1,b=2,c=3) creates a named list with elements named "a," "b," and "c," associated with values 1, 2, and 3, respectively. The correct answer to the question is Option C, denoting a named list. A named list in R can be used to store a collection of elements that can be accessed through their unique names.

Step-by-step explanation:

The question refers to an operation in the R programming language, where x <- list(a=1,b=2,c=3) is used to create a specific data structure. To address the question:

  • Option A suggests that a vector is created. However, in R, vectors do not hold names for their elements directly within the vector itself.
  • Option B suggests the creation of a data frame. While data frames can have column names, the use of the list() function does not create a data frame.
  • Option C is the correct option. The list() function in R creates a named list with elements "a", "b", and "c", each associated with the values 1, 2, and 3 respectively. The names within the list serve as identifiers for the elements they are associated with.
  • Option D suggests that a matrix with named rows and columns is created. This is incorrect, as the list() function does not create matrices.

Therefore, the correct answer is C) A named list with elements "a", "b", and "c".

To define the random variable X, we consider it as a function that assigns numerical values to each outcome in a sample space of a random experiment. The values X may take on are dependent on the specific experiment and its sample space. The distribution of X, often symbolized by 'X ~', indicates the probability of X assuming each of its possible values.

User Candi
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