Question 1
Question
Why should you use an ANOVA rather than a lot of T-tests?
Answer
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Performing lots of t-tests increases the probability of making a Type 1 error
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Performing lots of t-tests increases the probability of making a Type 2 error
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Performing lots of t-tests increases the chance of failing to reject a false null hypothesis
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All of the above
Question 2
Question
The ANOVA statistic is calculated by ____________
Answer
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Subtracting the between groups variance from the within groups variance
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Adding the between groups variance to the within groups variance
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Dividing the between groups variance by the within groups variance
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Multiplying the between groups variance by the within groups variance
Question 3
Question
You calculate an F ratio and get a value more than 1. How would you interpret this?
Answer
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There is more between groups variance than within groups variance
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There is the same amount of between groups variance as within groups variance
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There is less between groups variance than within groups variance
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There is no within groups variance
Question 4
Question
You have calculated the SSbetween as 10 and the SStotal as 15, what would the SSwithin be?
Question 5
Question
Your study has four conditions with 20 participants in each condition. What would the df-within be?
Question 6
Question
Which of the following is the correct way to calculate the MSbetween
Answer
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SSbetween / df-between
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SSbetween / SStotal
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SSbetween * df-between
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SSbetween * df-total
Question 7
Question
A researcher wants to see if caffeine improves mathematics ability. She randomly assigned participants to three treatment groups: no caffeine (control), 40mg of coffee, and 80mg of coffee. After the treatment, all participants took a maths test. A one-way ANOVA was performed on the data.
The output is shown below, but the F-value is missing. Using the other information in the table what should the F-value be?
Question 8
Question
What should the researcher conclude from the ANOVA results shown in question 7?
Answer
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There was a significant effect of treatment type on maths ability
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There was no significant effect of treatment type on maths ability
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Maths ability was significantly worse with no caffeine
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Caffeine significantly improves maths ability
Question 9
Question
What does the eta squared tell us?
Answer
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If there is a significant difference between groups
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How much variance in the dependent variable can be accounted for by the independent variable
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How much variance in the independent variable can be accounted for by the dependent variable
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If homogeneity has been established
Question 10
Question
If an author reports the results of an ANOVA as F (4, 65) = 9.56, p = 0.1, what is the between-groups degrees of freedom