Exam 1

  1. Metainformation

    Tag Value
    fileReliability_uu-reliability-015-en_uu-reliability-015-en
    nameuu-reliability-015-en
    sectionReliability
    typeschoice
    solutionFALSE, FALSE, TRUE, FALSE
    TypeCalculation
    LanguageEnglish
    LevelStatistical Literacy

    Question

    The Media & Entertainment Management (MEM) program at Inholland University of Applied Sciences was rated very weak by the Education Inspectorate in 2011. In response to this reporting, research is being conducted into student satisfaction with this program. An experimental test version consists of 20 equivalent items. The reliability rxx’ of this test is .85. For the real study, the researcher must shorten the test by removing five items.

    The estimated reliability of the scores of the shortened test (r ̂VVV’) is then:


    1. FALSE: Lower than .65
    2. FALSE: Between .65 and .75
    3. TRUE: Between .75 and .85
    4. FALSE: Higher than .85

    Solution

    Explanation: The formula for the extension factor is v - kk\frac {k'}{k} where k’is the number of questions on the new test (here 20-5=15 questions) and k is the number of questions on the original test (here:20). Filling in gives v= 1520=0.75\frac {15}{20}= 0.75

    The formula for the reliability of the extended test is $r_{xx’} = = = = 0.809 $

    Thus, the correct answer is Option C.