Instruction 11-2
a Realtor Wants to Compare the Average Sales-To-Appraisal

Instruction 11-2
A realtor wants to compare the average sales-to-appraisal ratios of residential properties sold in four neighbourhoods (A, B, C, and D) . Four properties are randomly selected from each neighbourhood and the ratios recorded for each, as shown below.
A: 1.2, 1.1, 0.9, 0.4 C: 1.0, 1.5, 1.1, 1.3
B: 2.5, 2.1, 1.9, 1.6 D: 0.8, 1.3, 1.1, 0.7
Interpret the results of the analysis summarised in the following table:
$$\begin{array} { | l | c | c | c | c | c | } \hline \text { Source } & \text { df } & \text { SS } & \text { MS } & \text { F } & \text { PR > F } \\\hline \text { Neighbbourhoods } & & 3.1819 & 1.0606 & 10.76 & 0.001 \\\hline \text { Error } & 12 & & & & \\\hline \text { Total } & & & & & \\\hline\end{array}$$
-Referring to Instruction 11-2,the among group degrees of freedom is

A) 4.
B) 16.
C) 3.
D) 12.