/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 13 Classify each of the following v... [FREE SOLUTION] | 91Ó°ÊÓ

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Classify each of the following variables as either categorical or numerical. For those that are numerical, determine whether they are discrete or continuous. a. Brand of computer purchased by a customer b. State of birth for someone born in the United States c. Price of a textbook d. Concentration of a contaminant (micrograms per cubic centimeter) in a water sample e. Zip code (Think carefully about this one.) f. Actual weight of coffee in a 1 -pound can

Short Answer

Expert verified
The variables are classified as follows: a. categorical, b. categorical, c. continuous numerical, d. continuous numerical, e. categorical, f. continuous numerical.

Step by step solution

01

Classifying a through d

Let's start by analyzing and classifying the varibles a through d. a. Brand of a computer is a categorical variable since brands cannot be quantified. b. State of birth for someone in the United States is also a categorical variable based on 50 distinct categories. c. Price of a textbook is a continuous numerical variable, it can take any positive real number. d. The concentration of a contaminant is also a numerical variable. More specifically, since the concentration can take any positive real value within a given range, it can be classified as continuous.
02

Classifying e and f

Let's proceed to classify the remaining variables, e and f. e. Zip code, though a number, is a categorical variable. This is because its numerical values don’t have a mathematical meaning, they serve merely as labels or codes. f. The actual weight of coffee in a 1-pound can is a numerical variable. Since, in theory, it could take any value between certain boundaries (probably slightly below and above one pound), it is a continuous variable. Note that the discretization of measures by the means' accuracy does not turn a numerically continuous variable into a discrete one.
03

Summary of Classified Variables

Finally, let's summarize all the variables identified and classified: Brand of computer - categorical; State of birth in the US - categorical; Price of a textbook - continuous numerical; Contaminant concentration - continuous numerical; Zip code - categorical; Actual weight of coffee - continuous numerical. Here it's important to note that the ability to correctly identify and classify variables is a fundamental first step in proper data analysis.

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