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Observations, unit of analysis, and variables

  1. Oct 9, 2014 #1
    1. The problem statement, all variables and given/known data

    Sun Tyrant: 25, 28, 25, 28, 29, 24, 28, 24, 24, 28, 30, 24, 22, 27

    Sun Acrid: 29, 31, 29, 26, 28, 22, 25, 29, 29, 27, 28, 23, 26, 29

    Laminatekist: 25, 26, 26, 26, 26, 28, 27, 26, 25, 28, 24, 28, 27, 25

    This data set shows the number of raisins in each of 14 boxes of three different brands of raisins. In this set of data, what is the unit of analysis, the observations, and the variables?

    2. Relevant equations


    3. The attempt at a solution

    I know the definitions of these terms, but in this instance I am having difficulty determining which term belongs to which part of the data. I think that the unit of analysis is raisins. The observations are the three companies, and the variable is the amount of raisins. At the same time though, I think that the observations could be the packages of raisins, but I am not sure...
  2. jcsd
  3. Oct 9, 2014 #2


    Staff: Mentor

    How are these units defined in your textbook? Does it provide any examples?
    For this problem, I think the unit of analysis is a box of raisins and each of the numbers represents one observation. Also, I think there are three random variables, which might give you a hint into my reasoning.
  4. Oct 9, 2014 #3
    There are examples in the book, but they are not in the format of this problem. They just give various lists of various characteristics of people and say that a person is the unit of analysis, the characteristics (like height and weight) are variables, and that a single row encompassing all of the characteristics is a single observation. This problem seems to be different. I now understand that a box of raisins is the unit of analysis, but my main confusion lies in what are the variables and observations. Is the number of raisins the variable and the brand the observations? Or is the brand the variable and the number of raisins each observation? In my book, a variable is defined as "any characteristic that varies between observation," so this leads me to believe that the number of raisins is a "characteristics" that varies between the observations. But this is still confusing to me...
  5. Oct 9, 2014 #4


    Staff: Mentor

    I might be off, but I believe that there are three variables: XST = the number of raisins in a box of Sun Tyrant raisins, and similar for XSA and XL. In an observation, you count the number of raisins in a given box of a certain brand.
  6. Oct 10, 2014 #5


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    Homework Helper

    I agree with Mark44. I also think that, if this is how the problem appears in the text, it is not very clearly written.
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