One-way ANOVA Quiz

Which one is not an assumption of the ANOVA test?

• Homogeneity of variance

• Normality

• Independence of observations

• Equal population size for group

Which one is not a test for normality?

• Skewness

• Kolmogorov-Smirnov

• Shapiro-Wilk

• T-test

Which one of the following is an estimation of the experimental error?

• Between-group mean square error

• Within-group mean square error

• Total mean square error

• Between-group sum of squares

Which type of error can you reduce or avoid while designing the experiment?

• Individual differences error

• Measurement error

• Mean square error

• Experimental error

Which one is not a data transformation appropriate for recovering normality?

• Square root

• Logarithmic

• Reciprocal

• Inverse

The significance value alpha represents:

• Type I error

• Type II error

• Power

• Probability that the null hypothesis is true

What is the relationship between total, within-group and between-group deviation?

• Total deviation = within-group deviation - between-group deviation

• Between-group deviation = total deviation - within-group deviation

• Within-group deviation = total deviation + between-group deviation

• Between-group deviation = total deviation + within-group deviation

Consider a test with one independent variable and four levels. Each level has a sample of size 5. How much is the between-group degrees of freedom?

• 3

• 4

• 16

• 19

What set of parameters do you need to determine the critical F-value?

• Alpha, within-group df, between-group df

• Alpha, number of levels, within-group df

• Number of levels, within-group df, between-group df

• Alpha, number of levels, between-group df

In an ANOVA study, you have three groups:

• Group 1 (n=20): z=1.8 (minor skewness)

• Group 2 (n=20): z=0.8 (no skewness)

• Group 3 (n=20): z=2.4 (substantial skewness)

What should you do?

• No transformation needed, sample size is large.

• Transform all groups

• Transform only Group 3

• Use non-parametric test