Latin Square Design Price Valuations for 8 Varieties of Tea, Prepared on 8 Days in 8 Orders Harrison and Bose (1942), Sankhya, Vol6,#2,pp

Data Description Response: Mean Price Valuation among 6 judges 8 Tea Varieties (Crossing of Seed and Field Type):  4 jats (tea seed) – BJ,KK,PG,CH  2 Field Types - Pruned previous December, Unpruned 8 Dates of Manufacture (7/28 – 9/29) 8 Orderings of Preparation All varieties prepared on each date All varieties receive each order position of preparation

Order of Manufactured Samples, Valuations, Means

Latin Square Design - Model Model (8 Varieties, Dates, Orders, N=8 2 =64) :

Latin Square Design - ANOVA & F-Test Note: We can partition Variety SS into main effects for jat and pruning, and their interaction (next slide)

Decomposing Variety Sum of Squares

Analysis of Variance Evidence of Jat and Pruning Main Effects, Interaction not significant at 0.05 significance level

Pairwise Comparison of Jat Means Tukey’s - q from Studentized Range Dist. k=4,  = (t-1)(t-2)=42 Note: Each Jat Mean is based on 2t=16 observations Bonferroni’s Method - t-values from table on class website with n = (t-1)(t-2)=42 and C=4(4-1)/2=6 Very close to significant difference

Relative Efficiency Relative Efficiency of LS to CRD (how many times as many replicates would be needed for CRD to have as precise of estimates of treatment means as LS does): Would need approximately 56 reps per variety to have as precise of estimates of variety means if experiment conducted as completely randomized design