Experimental Analysis
1. **Problem 3: Analyze the 4x4 Latin Square Design for assembly methods and operators (α = 0.05).**
Given a Latin square for assembly method (A, B, C, D) by 4 operators with time data for assembly, we want to analyze the effect of method on assembly time accounting for operator and order effects.
2. **Arrange data:**
Order 1: C=10, D=14, A=7, B=8
Order 2: B=7, C=18, D=11, A=8
Order 3: A=5, B=10, C=11, D=9
Order 4: D=10, A=10, B=12, C=14
3. **Sum totals and squares:** Calculate grand total, row sums (order), column sums (operator), and treatment sums (method). Compute sum of squares for total, rows, columns, treatments, and error.
4. **Conduct ANOVA:**
- Total degrees of freedom (df) = $n^2 -1 = 16-1=15$
- Row df = $n-1=3$
- Column df = $n-1=3$
- Treatment df = $n-1=3$
- Error df = $(n-2)(n-1)= (4-2)(4-1)=2\times 3=6$
5. **Calculate Mean Squares (MS) and F-values** for rows, columns, and treatments.
6. **Compare F calculated for treatments** with F critical at α=0.05 and df=(3,6). From F-tables, critical F approx 4.76.
7. **Conclusion:** If $F_{treatment} > 4.76$, the assembly method significantly affects time. Otherwise, no significant effect.
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8. **Problem 4: Analyze Graeco-Latin square design incorporating workplace as an additional source of variation (α = 0.05).**
Data given for 4 assembly methods, 4 operators, and 4 workplaces in a Graeco-Latin square.
9. **Arrange and label data:**
E.g. Order 1: Cβ=11, Bγ=10, Dδ=14, Aα=8, etc.
10. **Set factors:** Method (A,B,C,D), Operator, Workplace (α, β, γ, δ), and Order
11. **Perform GLSD ANOVA by calculating sums of squares for each factor and residual, then compute mean squares and F-values. Use df for each factor = 3.
12. **Check significance of treatments** (assembly methods) and the new factor workplace.
13. **Conclusion:** If treatment or workplace F > critical F (4.76 at α=0.05, df=3,9 or 3,6 depending on design), conclude significant effects.
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14. **Problem 5: Analyze the Balanced Incomplete Block Design (BIBD) for seven hardwood concentrations over seven days (α = 0.05).**
15. **Data matrix:** Hardwood concentrations 2,4,6,8,10,12,14 with yields on days 1-7 (some missing due to incomplete design).
16. **Calculate totals:** Sum of observations, treatment totals (concentrations), block totals (days), total number of observations.
17. **Calculate parameters of BIBD:** Number of treatments $v=7$, block size $k=3$, number of blocks $b=7$ runs, replication number $r$ (number of blocks each treatment appears in).
18. **Compute sum of squares for treatments, blocks, total, and error** using formulas for BIBD.
19. **Conduct ANOVA:** calculate mean squares, F-values, and compare treatment F-value to F critical (at df = v-1 = 6, error df).
20. **Conclusion:** Determine if hardwood concentration significantly affects paper strength at $=0.05$.
**Final conclusions:** Statistical tests will reveal whether assembly method, workplace, and hardwood concentration have significant effects considering operators, order, and blocks. This improves understanding of factors influencing assembly time and paper strength.