Maddox Smith Staff asked 4 years ago

Highlighting Any Similarities or Differences

1.                  Describe the sources of variability present in each data set of Experiment 1. Then using appropriate data displays, describe each data set in Experiment 1, highlighting any similarities or differences that may exist between the 2 stirring rates.                             [20 %]   2.                  Using the data sets collected in Experiment 1, construct an appropriate parametric and non-parametric test to assess the claim that the typical particle size is not the same for each rate of stirring. When writing up your analysis of this claim state any assumptions that need to be made in conducting these tests and if appropriate carry out tests to validate these assumptions. Discuss also the advantages and disadvantages of each test.                      [20 %]   3.                  Using the data set collected in Experiment 2 and the technique of multiple least squares, estimate the b parameters of the following second order response surface model:                         where Y is particle size, X1 is the stirring rate, X2 is the Tween 80 concentration, X3 is the Chitosan concentration, and X4 is the glutaraldehyde concentration. e is the prediction error or residual. When writing up your analysis of this model, describe how well this model fits the data, which variables are statistically significant (important) and what meanings can be attached to the b parameters. State any assumptions that need to be made is assessing such statistical significance, and if appropriate carry out tests or construct scatter plots to validate these assumptions.                                                                                                            [30 %] 4.         Derive a simplified version of the above model that includes only the statistically significant variables.   When writing up your analysis, describe how well this simplified model fits the data, the meaning of the parameters, the degree of accuracy achievable when predicting the particle size using this simplified model (as described by a 95 confidence interval on an actual v prediction plot). Use the model to find the process conditions required for small (< 0.25 mm) and large particle sizes (> 0.53 mm), making full use of any suitable 2D or 3D scatter plots to explain these conditions.                                                                                                   [30 %]