Is alpha (α) in a central composite design higher or lower?
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In the context of central composite designs (CCDs), the value of alpha (α) can vary depending on the specific design and optimization criteria. Studies have explored the efficiencies of CCDs in comparison to other designs like orthogonal array composite designs (OACDs). The positioning of levels, such as factorial and axial levels, is crucial for second-order response surface modeling in CCDs. Comparative evaluations of different varieties of CCDs have shown that replicating star points can impact the optimality criteria, with varying effects on D, A, G, and IV-optimality. Additionally, alpha estimation procedures have been outlined for complex sample designs, aiding in coefficient alpha estimation and instrument revision assessments. Therefore, the value of alpha in a central composite design can be influenced by the specific design parameters and optimization goals.
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16 Citations | In a complex sample design, coefficient alpha (α) can be estimated for multiple-component measuring instruments, aiding in scale development; however, the paper does not compare alpha in central composite designs. |
Open access•Journal Article | In a central composite design, alpha (α) is kept constant at all points equidistant from the center, making it higher to maintain rotatability, as discussed in the paper. |
01 Jan 2020 2 Citations | The paper discusses the efficiency of central composite designs for various values of α in star points, without specifying if α is higher or lower. |
1 Citations | In a central composite design, alpha (α) encompasses both factorial and axial levels, crucial for response surface modeling and optimization, without a specific indication of being higher or lower. |
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