QUESTION IMAGE
Question
- a researcher reports an f - ratio with $df = 4,62$ from an independent - measures research study.
a. how many treatment conditions were compared in the study?
b. what was the total number of participants in the study?
c. use appendix b to find the critical value for f. use $\alpha=.05$.
d. what is the critical region for $\alpha =.01$?
Part (a)
Step1: Recall df between groups formula
For an independent - measures ANOVA, the degrees of freedom between groups (numerator degrees of freedom for the \(F\) - ratio) is given by \(df_{between}=k - 1\), where \(k\) is the number of treatment conditions.
We know that \(df_{between} = 4\) (from the \(df = 4,62\) where the first value is \(df_{between}\) and the second is \(df_{within}\)).
Step2: Solve for k
We have the equation \(k-1 = 4\).
Adding 1 to both sides of the equation, we get \(k=4 + 1=5\).
Step1: Recall df within groups formula
For an independent - measures ANOVA, the degrees of freedom within groups (denominator degrees of freedom for the \(F\) - ratio) is given by \(df_{within}=N - k\), where \(N\) is the total number of participants and \(k\) is the number of treatment conditions.
We know that \(df_{within}=62\) and from part (a) we found that \(k = 5\).
Step2: Solve for N
We have the equation \(N - 5=62\).
Adding 5 to both sides of the equation, we get \(N=62 + 5 = 67\).
Step1: Identify df values
We have \(df_{between}=4\) and \(df_{within}=62\), and \(\alpha = 0.05\).
Step2: Use F - distribution table
When using the \(F\) - distribution table (Appendix B), for \(\alpha=0.05\), \(df_1 = 4\) (numerator degrees of freedom) and \(df_2=62\) (denominator degrees of freedom). Since 62 is not a common value in some tables, we can use the approximation for large \(df_2\) or use the table value for \(df_2=\infty\) as an approximation (or use a more detailed table). The critical value for \(F\) with \(df_1 = 4\) and \(df_2 = 62\) (or approximated with \(df_2=\infty\)) at \(\alpha = 0.05\) is approximately 2.52 (if we use \(df_2 = 60\), the value is 2.52; for \(df_2=\infty\), it is 2.41, but a more accurate value using a calculator or a detailed table for \(df_2 = 62\) is close to 2.52).
Snap & solve any problem in the app
Get step-by-step solutions on Sovi AI
Photo-based solutions with guided steps
Explore more problems and detailed explanations
5