Week 3 Flashcards
Complete randomisation ensures
We get min variance linear unbiased estimators of parameters and functions of parameters
Advantage of blocking
Variance in responses between blocks can be separated from variance between units within blocks
Randomised complete block design
Each block has exactly one instance of each treatment which is randomly assigned to a unit (blocks size is equal to number of treatments)
Systematic design
Treatments are allocated in ascending order across numbered units
What is?
b_i is the average deviation of block i from the mean
e_ij represents the deviation of unit j from block i from the mean of that block
1/t
This is allocation of treatment k on unit j in block i
0
Since each treatment can only occur on one unit in block i
1/(t-1)
Since one treatment has already been allocated in block i
ANOVA for RCBD under finite population model
Where
yik = μ + bi + tk + Σj δijk eij
Treatment total for treatment k
Sum of responses under treatment K across each block
E[T_k] = ?
Comparing expectations of treatment totals
Variance of treatment total
Given a systematic design. What is Randomisation procedure for 2 treatment factors. 4 complete blocks. Each factor has 3 levels
Within each block independently, choose a random permutation of 6 objects and assign it to levels of both factors
Each treatment pair in systematic design should be fixed to ensure each combination is tested