FieldsAgriculture and horticulture
Experiments here usually have about 3 factors and 14 runs. Full factorials and response surface designs are the most common.
- Full factorial
- Fractional factorial or screening
- Central composite or Box-Behnken
- Mixture
- Other designs
Show the numbers
| Kind of design | Experiments | Factors | Runs |
|---|---|---|---|
| Full factorial | 7 | 2 | 6 |
| Fractional factorial or screening | 1 | 3 | 4 |
| Central composite or Box-Behnken | 5 | 3 | 20 |
| Mixture | 1 | 3 | 12 |
| Other designs | 2 | 2 | 22.5 |
Factors and runs are the medians of each kind.
Full factorial
Every combination of the factor levels.
- Antowan's spinach seeds: amount of water W and sunlight S, and their interaction plotDunn (2015) · 2 factors, 4 runs
- Pea plants: amount of soil A and daily water B, and the prediction at the baselineDunn (2015) · 2 factors, 4 runs
- Soil solarization: period P and plastic thickness T, and the contour plot of their 2^2 factorialDunn (2015) · 2 factors, 4 runs
- Soil solarization: period P and plastic thickness T, then a centre point and a run at 8 weeks in P onlyDunn (2015) · 2 factors, 6 runs
- Shell weight of eggs as a percentage of egg weight against dietary calcium and phosphorus, a 3^2 with three hens' eggs at each diet (Exercise 11.23)Box and Draper (2007) · 2 factors, 9 runs
Show the rest
- Yield of lima beans: depth of planting, watering and type of bean, three replications (Exercises 10.4 and 10.5)Box, Hunter and Hunter (1978) · 3 factors, 24 runs
- Two nitrogen fertilizers at three levels in all nine combinations: balanced in the amounts, very unbalanced in their total and ratioBox and Draper (2007) · 2 factors, 9 runs
Fractional factorial or screening
A planned part of the combinations, to find the factors that matter.
Central composite or Box-Behnken
Extra runs that fit curvature, to find an optimum.
- Exercise 12.8: ridge path of maximum yield of lettuce tops for Exercise 11.22's surface (source 1)Box and Draper (2007) · 3 factors, 20 runs
- Survival of motile bovine spermatozoa after storage against sodium citrate, glycerol and equilibration time, a composite design with α = 2 (Exercise 11.7)Box and Draper (2007) · 3 factors, 15 runs
- Yield of lettuce tops against copper, molybdenum and iron, a composite design with x3 = -0.5 in place of -1, for four sources of nitrogen and iron (Exercise 11.22)Box and Draper (2007) · 3 factors, 20 runs
- Yield of tomato tops in Castor silt loam: a replicated composite design and a wider 3^3 factorial that encloses it (Exercise 11.9)Box and Draper (2007) · 3 factors, 42 runs
- Yield of tomato tops in North Gower clay loam against nitrogen, phosphorus and potassium: a replicated composite design enclosed in a replicated 3^3 (Exercise 11.8)Box and Draper (2007) · 3 factors, 33 runs
Mixture
The ingredients add up to the whole.
Other designs
Optimal, blocked, split-plot and other designs made for the problem.
- Yield of an agronomic trial in a dodecahedron design with ten centre points in five orthogonal blocks, two replicates (Exercise 7.24)Box and Draper (2007) · 3 factors, 30 runs
- Soil nitrogen by five operators on three days, a sample each day split among them (Problem 9 of Part II)Box, Hunter and Hunter (1978) · 1 factor, 15 runs