Exhibit 7-7: A group of curriculum designers has developed a new system for teaching phonics to young children.They randomly selected 24 kindergarten students to receive either the old phonics method or the new phonics method.The designers realized that kindergartens have morning and afternoon classes, so they wanted to build this factor into the research design.The following is the mean, standard deviation, and number for each group.
$ \begin{array}{lll}\text { Morning } & {\text { Old }}{} & {\text { New }}{} \ & 16.33 & 13.50 \ &1.03 & 2.74 \& 6 & 6 \ \text { Afternoon } & 13.17 & 16.83 \ & 3.55 & 2.14 \ & 6 & 6\end{array} $
The following is an incomplete summary table of the analysis of variance:
$\begin{array}{ll}
\underline { \text { Source }} & \underline { \text { SS }} & \underline { \text { df }} & \underline { \text { MS}} & \underline { \text { F}}\
\text { Time of Day } & 0.042 \
\text { Lesson Design } & 1.042 \
\text { Interaction }\
\text { Error } & 128.500 \
\text { Total } & 102950
\end{array}$
-Refer to Exhibit 7-7.What are the degrees of freedom for Lesson Design?
A) 1
B) 2
C) 20
D) 24

Question

Exhibit 7-7: A group of curriculum designers has developed a new system for teaching phonics to young children.They randomly selected 24 kindergarten students to receive either the old phonics method or the new phonics method.The designers realized that kindergartens have morning and afternoon classes, so they wanted to build this factor into the research design.The following is the mean, standard deviation, and number for each group.
$ \begin{array}{lll}\text { Morning } & {\text { Old }}{} & {\text { New }}{} \ & 16.33 & 13.50 \ &1.03 & 2.74 \& 6 & 6 \ \text { Afternoon } & 13.17 & 16.83 \ & 3.55 & 2.14 \ & 6 & 6\end{array} $
The following is an incomplete summary table of the analysis of variance:
 $\begin{array}{ll}
\underline { \text { Source }} & \underline { \text { SS }} & \underline { \text { df }} & \underline { \text {  MS}} & \underline { \text {   F}}\
\text { Time of Day } & 0.042 \
\text { Lesson Design } & 1.042 \
\text { Interaction }\
\text { Error } & 128.500 \
\text { Total } & 102950
\end{array}$
-Refer to Exhibit 7-7.What are the degrees of freedom for Lesson Design?
A) 1
B) 2
C) 20
D) 24

Quizplus · Accepted Answer

The degrees of freedom (df) for Lesson Design in an ANOVA table is calculated based on the number of levels of the factor minus one. Since there are two methods of phonics teaching (old and new), the levels of the Lesson Design factor are 2. Therefore, the degrees of freedom for Lesson Design is $2 - 1 = 1$.

Exhibit 7-7: a Group of Curriculum Designers Has Developed a New