Exam 1

  1. Metainformation

    Tag Value
    fileInferential_Statistics_eur-inferential_statistics-207-en_eur-inferential_statistics-207-en
    nameeur-inferential_statistics-207-en
    sectionInferential Statistics/Parametric Techniques/Correlations/Pearson, Reliability/Analysis/Cronbach's alpha
    typenum
    solution0.71
    tolerance0
    TypeCalculate
    ProgramCalculator
    LanguageEnglish
    LevelStatistical Literacy

    Question

    A researcher investigates the relationship between depression and sleeping problems using a sample of 55 participants. The reliability of the depression scale is high, Rxx=.82. However, sleeping problems are more difficult to measure and the reliability of this scale is Ryy=.62.

    Calculate the maximum possible correlation the researcher can expect between depression and sleeping problems. Round to two decimals.

    Use the formula: rXoYo=rXtYt×RXXRYYr_{XoYo} = r_{XtYt} \times \sqrt {R_{XX}R_{YY}}


    Solution

    The maximum correlation that can be obtained is the square root of the product of the two reliabilities times 1 (the true score correlation). Thus, the maximum correlation is: rmaxXoYo=1RxxRyy=.82×.62=.71rmax_{XoYo} = 1 \sqrt{R_{xx}R_{yy}} = \sqrt {.82 \times .62} = .71