#1
Which of the following is a measure of central tendency?
Mean
ExplanationThe mean is a measure of central tendency that represents the average of a set of values.
#2
What is the purpose of a control group in an experiment?
To provide a comparison for evaluating the effect of the independent variable
ExplanationA control group serves as a baseline for comparison, allowing researchers to isolate and measure the impact of the independent variable.
#3
Which of the following is NOT a measure of dispersion?
Median
ExplanationThe median is a measure of central tendency, not dispersion. Measures of dispersion quantify the spread or variability of a dataset.
#4
What is the purpose of the null hypothesis in hypothesis testing?
To suggest that there is no effect or no difference in the population
ExplanationThe null hypothesis posits no effect, serving as a baseline for comparing observed results and determining statistical significance.
#5
What is the purpose of a one-way ANOVA test?
To compare the means of three or more independent groups
ExplanationOne-way ANOVA assesses whether there are statistically significant differences in means across three or more independent groups.
#6
What is the purpose of randomization in experimental design?
To ensure that every participant has an equal chance of being assigned to each experimental condition
ExplanationRandomization minimizes selection bias and enhances internal validity by distributing potential confounding variables equally across experimental groups.
#7
Which statistical test is appropriate for comparing the means of two independent groups?
Independent t-test
ExplanationThe Independent t-test assesses whether there is a significant difference between the means of two independent groups.
#8
What is the purpose of statistical power in hypothesis testing?
To assess the probability of correctly rejecting a false null hypothesis
ExplanationStatistical power indicates the likelihood of detecting a true effect, minimizing the risk of Type II errors.
#9
Which statistical test is appropriate for analyzing the relationship between two categorical variables?
Chi-square test
ExplanationThe Chi-square test is used to assess the association between two categorical variables by comparing observed and expected frequencies.
#10
Which of the following is a non-parametric statistical test?
Mann-Whitney U test
ExplanationThe Mann-Whitney U test is a non-parametric test used to compare the distributions of two independent groups when assumptions of parametric tests cannot be met.
#11
What is the purpose of blocking in experimental design?
To control for extraneous variables by forming homogeneous groups
ExplanationBlocking involves grouping participants based on specific characteristics to reduce variability and enhance the precision of experimental results.
#12
What is the purpose of a factorial design in experimental research?
To examine the effects of multiple independent variables and their interactions
ExplanationFactorial designs allow researchers to study the impact of two or more independent variables simultaneously, including their interactions.
#13
What is the purpose of blinding in experimental design?
To prevent experimenter bias and participant expectancy effects
ExplanationBlinding ensures that both participants and experimenters are unaware of group assignments, minimizing the potential for bias in results.
#14
Which of the following is NOT an assumption of the independent samples t-test?
Equal sample sizes
ExplanationWhile equal sample sizes can be an assumption, it is not a necessary one for the independent samples t-test. The key assumptions include normality and homogeneity of variances.
#15
What is the purpose of post-hoc tests in ANOVA?
To compare all possible pairs of means after finding a significant result in ANOVA
ExplanationPost-hoc tests help identify which specific group means differ from each other after obtaining a significant result in ANOVA.