307 Diamonds Were Sampled and Randomly Sorted into Three Groups

question 70

Multiple Choice

307 diamonds were sampled and randomly sorted into three groups of diamonds. These diamonds were randomly assigned to one of the three organizations, or groups (HRD, GIA, or IGI) , that certify the appraisal of diamonds. A study was conducted to determine if the average size of diamonds reported by these three certification groups differ. A completely randomized design was used and the resulting ANOVA table is shown below. $$\begin{array}{l}\text { One-Way AOV for CARAT by CERT }\\\begin{array} { l c c c c c } \text { Source } & \text { DF } & \text { SS } & \text { MS } & \text { F } & \text { P } \\\hline \text { CERT } & 2 & 8.3265 & 4.16326 & 83.21 & 0.0000 \\\text { Error } & 305 & 15.2604 & 0.05003 & & \\\text { Total } & 307 & 23.5869 & & &\end{array}\end{array}$$ Give a practical conclusion for the test in the words of the problem. Use ? = 0.10 to make your conclusion.

• A) There is sufficient evidence to indicate that the mean carat weight for the HRD group equals the mean carat weight for the IGI group.
• B) There is insufficient evidence to indicate that differences exist among the mean carat weights for the three certification groups.
• C) There is sufficient evidence to indicate that differences exist among the mean carat weights for the three certification groups.
• D) There is sufficient evidence to indicate that the mean carat weight for the GIA group is lower than the other two groups.

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Definitions:

Correlational Studies

Research methodologies that examine the relationships between two or more variables to determine if and how they are associated.

Experimental

Pertaining to a method of testing hypotheses through controlled procedures to determine cause and effect relationships.

Personality Trait

Enduring patterns of thoughts, feelings, and behaviors that distinguish individuals from one another.

Nominal Scale

A scale of measurement used in research that involves categorizing variables into non-numerical categories without a defined order or hierarchy.