Exam 1

  1. Metainformation

    Tag Value
    fileInferential_Statistics_vufsw-independent_samples_means-1249-en_vufsw-independent_samples_means-1249-en
    namevufsw-independent samples means-1249-en
    sectioninferential statistics/parametric techniques/t-test/independent samples means
    typeschoice
    solutionTRUE, FALSE, FALSE, FALSE
    Typecalculation
    Programcalculator
    LanguageEnglish
    Levelstatistical literacy

    Question

    The following (abrived) news message appeared on NU.nl (9 juli 2014).

    Robben is more often a victim of fouls at the World Cup 
    Arjen Robben is more often a victim of fouls committed at the World Cup than during the qualifying round of the Dutch squad. 
In the five games that 30-year-old attacker has played in Brazil, 22 times a foul was committed on him. That is an average of 4.4 per match. 
During the six World Cup qualifying matches of Robben, which he played against Romania, Hungary and twice against Estonia and Turkey, the total number of fouls committed on him was only eleven. 
The average with 1.8 fouls per game is therefore much lower.

    A researcher tests the statement in the article about the higher number of fouls per game committed on Robben at the World Cup. Suppose the standard deviations are also known.
    These are the data for the World Cup qualifiers: ; ; . These are the data for the World Cup matches: ; ; .

    Test with alpha= 0,05. Is the number of fouls committed on Robben during the WC (group 2) significantly higher than during the qualification matches (group 1)?


    1. TRUE: Yes, because the critical t-value is 1.83 and the observed absolute t-value is 2.40.
    2. FALSE: Yes, because the critical t-value is 1.83 and the observed absolute t-value is 2.60.
    3. FALSE: Yes, because the critical t-value is 2.26 and the observed absolute t-value is 2.40.
    4. FALSE: Yes, because the critical t-value is 2.26 and the observed absolute t-value is 2.60.

    Solution

    It is significant different because the critical t-value is 1.83 and the observed absolute t-value is 2.40.

    The critical t value can be found in the table (df=11-2=9) in the table. The absolute t value can be calculated with:

    se=1,083, thus (4,40-1,80)/ 1,083= 2,40.


    1. True
    2. False
    3. False
    4. False