3. Elements of Design of
Experiments
1. Conjecture or hypothesis
2. Response variable
3. Factors, levels and ranges
4. Treatments of factors
5. Blockings
6. Tools and methods for experiments and
measurements
7. Effect models (independent or interaction factors)
8. Replication, randomization and local factor
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6. Experiment with a Single Factor
Experiment with a single factor is an
experiment conducted by deliberately
changing a single factor of interest at an
arbitrary a levels of the factor (a treatments).
Simple comparative experiment is a single
factor experiment to compare 2 levels of the
factor (2 treatments).
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10. Completely Randomized Design
Completely Randomized Design is a type of
experimental design in which the treatments
or design factors are assigned to the
experimental units in a random manner. In
designed experiments, a completely
randomized design results from running all of
the treatment combinations in random order.
So that the environment in which the
treatments are applied is as uniform as
possible.
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28. Model Adequacy Checking
Normal Probability Plot of the Residuals
Plot of Residuals in Time Sequence
Plot of Residuals versus Fitted Values
Plot of Residuals versus Other Variables
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33. Practical Interpretation of Results
A Regression Model
Comparisons Among Treatment Means
Graphical Comparisons of Means
Contrasts
Orthogonal Contrasts
Scheffé’s Method for Comparing All Contrasts
Comparing Pairs of Treatment Means
Tukey’s Test
Tukey–Kramer procedure
The Fisher Least Significant Difference (LSD) Method
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