Download presentation
Presentation is loading. Please wait.
2
Unsorted Treatments Random Numbers 1 0.533 1 0.683 2 0.702 2 0.379 3 0.411 3 0.962 3 0.139 Sorted Sorted Experimental Treatments Random Units Numbers 3 0.139 1 2 0.379 2 3 0.411 3 1 0.533 4 1 0.683 5 2 0.702 6 3 0.962 7 Randomization
3
Bread Rise Experiment 1. Mix The Dough 2. Divide the dough into 12 small loaves of the same size. 3. Randomly assign 4 loaves to rise 35 minutes, 4 to rise 40 minutes, etc. 4. After allowing each loaf to rise the specified time, measure the height of the loaf.
11
Model for CRD Design Cell Means Model
12
Alternate Model Effects Model
13
Notation Sample means Grand Mean
14
Least Squares Estimates Cell Means Choose estimates to minimize
15
Matrix Notation for Alternate Model LS Estimators are solution to Problem is singular
16
SAS proc glm Non-singular
17
is a generalized inverse for Biased Estimates
18
Bread Rise Experiment
22
= ^
23
:
24
Matrix Notation for Estimable Functions is an unbiased estimator for when the rows of L are linear combination of the rows of for example
25
is a linear
30
ssE must represent varation in experimental units not subsamples, repeated measures or duplicates Teaching Example (illustration of problems) Classes randomized to different teaching methods experimental unit=class No replicate classes no way to compute ssE Teaching method confounded with difference in classes Use of student to student variability (i.e. subsamples) to calculate ssE Could be totally misleading
31
● Independence of error terms ε ij ● Equality of variance across levels of treatment factor ● Normal distribution of ε ij
32
Check equal variance assumption 1. plot data vs treatment factor level 2. plot residuals vs predicted values or cell means
34
Check normality with normal plot of residuals
35
ods graphics on; proc glm data=bread plots=diagnostics; class time; model height=time/solution; run; ods graphics off;
40
λ = 1 -1.294869
43
Solutions►Analysis►Design of Experiments Two-Level Factorial Response Surface MixtureMixed-Level Factorial Optimal Design Split-Plot Design General Factorial
44
Define Variables►Add> ►Add qualitative factorial variable
45
Customize…►Replicate Runs Edit Responses… Design►Randomize Design …
46
Fit …
47
Model ► Fit Details…Model►Check Assumptions►Perform Residual AnalysisModel►Check Transformation►Box-Cox Plot
51
Teaching Experiment Objective: Compare student satisfaction between 3 different teaching methods Experimental unit: class Two replicate classes for each teaching method. Response: rating given by each student, summarized over class as multinomial vector of counts
55
power, 1-β practical significance
56
power Size of a practical difference
67
3. H 0 : μ 3 = μ 4 Does a mix of artificial fertilizers enhance yield? Is there a difference in plowed and broadcast? Does Timing of Application change Yield?
71
^^ Option 1Option 2
72
Option 1
73
Option 2
77
Review Important Concepts Experimental Unit Randomization Replication Practical Difference Determining the number of replicates by calculating the power
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.