5-Factor Experiment

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5-Factor Experiment

• Flavor Scores for Potatoes
• A. Mackey and J. Stockman (1958). Cooking
  Quality of Oregon-Grown Russet Potatoes,
  American Potato Journal, Vol.35, pp.395-407

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Data Description

• Response Flavor Score (Mean of 5 judges/4 reps)
• Factors
• Grow Area (1Southern OR, 2Central OR)
• 2-Week Holding Temp (175F, 240F)
• Potato Size (1Large, 2Medium)
• Storage Period (10months, 22m, 34m, 46m)
• Cook Method (1Boil,2Steam,3Mash,4Bake350,5Bak
  e450)
• N2x2x2x4x5160 sample measurements

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Factor Level (Marginal) Means (Overall2.91125)
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2-Factor Interaction Grow area x Storage Period
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Statistical Model (Fixed Effects)
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Formulas for Sums of Squares
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Analysis of Variance (Main Effects)
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Analysis of Variance (2-Factor Interactions)
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Analysis Of Variance (3-Factor Interactions)
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Interpretations

• Two 3-Factor Interactions are Significant
• Grow Area/Size/Storage Period
• Grow Area/Storage Period/Cooking Method
• Seven 2-Factor Interactions are Significant
• Note though that with 3-Factor Interactions being
  significant, many of 2-Factor Interactions differ
  among levels of 3rd Factor
• Four Main Effects are Significant
• Similar Caveats as for 2-Factor Interactions

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Grow Area/Size/Storage Period Interaction
Southern OR
Central OR
Small Large
Small Large
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Grow Area/Storage Period/Cooking Method
Interaction
Southern OR
Central OR
0m 2m 4m 6m
0m 2m 4m 6m