Research results suggest that IQ scores for boys are more variable than IQ scores for girls (Arden & Plomin, 2006). A typical study looking at 10-year-old children classifies participants by gender and by low, average, or high IQ. Following are hypothetical data representing the research results. Do the data indicate a significant difference between the frequency distributions for males and females? Test at the .05 level of significance and describe the difference.
Boys IQ: Low 18 Average 42 High 20
Girls IQ: Low 12 Average 54 High 14
This solution provides a step-by-step method for performing a Chi-square hypothesis test. All the steps of hypothesis testing, including the formulation of the null and alternate hypotheses, selection of the significance level, calculations of expected frequencies, and the calculation of the chi-square value, have all been explained so that a decision regarding the null hypothesis can be made. This is all completed within a Word document which has been attached.