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MANE 6313

Week 7, Module F

Student Learning Outcome

  • Select an appropriate experimental design with one or more factors,
  • Select an appropriate model with one or more factors,
  • Evaluate statistical analyses of experimental designs,
  • Assess the model adequacy of any experimental design, and
  • Interpret model results.

Module Learning Outcome

Analyze a Single Replicate of a 2k with Center Points using Minitab

Resources for the Week 7, Module F micro-lecture are:


Adding Center Points

  • Good idea if possible. Allows test for non-linearity.

  • Notation

\[ \begin{aligned} n_c&-&\mbox{number of center points}\\ n_f&-&\mbox{number of observations at factorial points}\\ \bar{y}_f&-&\mbox{the average value at the factorial points}\\ \bar{y}_c&-&\mbox{the average value at the center point} \end{aligned} \]

Test for Pure Quadratic Curvature

  • A second-order response model is defined to be
\[ y=\beta_0+\sum_{j=1}^k\beta_jx_j+\sum_{i<j}\sum\beta_{ij}x_ix_j+\sum_{j=1}^k\beta_{jj}x_j^2+\varepsilon \]
  • Notice the model contains interaction terms and pure quadratic terms

  • Tests the hypothesis that \(H_0:\sum_{j=1}^k\beta_{jj}=0\) vs. \(H_1:\sum_{j=1}^k\beta_{jj}\neq 0\)

  • Calculate one degree of freedom sum of squares for pure quadratic curvature

\[ SS_{\mbox{pure quadratic}}=\frac{n_cn_f(\bar{y}_f-\bar{y}_c)^2}{n_f+n_c} \]
  • Perform \(F\) test

Problem 6.35

problem 6.35, part one


problem 6.35, part two