Difference between revisions of "Worksheets/Week4"
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# Define the 3 factors. This code is a template that you | # Define the 3 factors. This code is a template that you | ||
# can easily extend and reuse for full factorial designs: | # can easily extend and reuse for full factorial designs: | ||
base | base = c(-1, +1) | ||
design | design = expand.grid(A=base, B=base, C=base) | ||
A | A = design$A | ||
B | B = design$B | ||
C | C = design$C | ||
# Type "A", and "B" and "C" at the command prompt | # Type "A", and "B" and "C" at the command prompt | ||
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# The response: stability [units=days] | # The response: stability [units=days] | ||
y | y = c(40, 27, 35, 21, 41, 27, 31, 20) | ||
# Linear model to predict stability from | # Linear model to predict stability from | ||
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# B: feed concentration: -1 == 5%; +1 == 15% | # B: feed concentration: -1 == 5%; +1 == 15% | ||
# C: mixer type: -1 = R mixer; +1 = W mixer | # C: mixer type: -1 = R mixer; +1 = W mixer | ||
model.stability | model.stability = lm(y ~ A*B*C) | ||
summary( | summary(model_stability) | ||
# Uncomment this line if you run the code in RStudio | # Uncomment this line if you run the code in RStudio | ||
| Line 100: | Line 100: | ||
source('https://yint.org/paretoPlot.R') | source('https://yint.org/paretoPlot.R') | ||
source('https://yint.org/contourPlot.R') | source('https://yint.org/contourPlot.R') | ||
paretoPlot( | paretoPlot(model_stability) | ||
# Uncomment these two lines later to inspect the | # Uncomment these two lines later to inspect the | ||
# contour plots | # contour plots | ||
#contourPlot( | #contourPlot(model_stability, 'A', 'B') | ||
#contourPlot( | #contourPlot(model_stability, 'A', 'C') | ||
# Make a prediction with this model: | # Make a prediction with this model: | ||
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xB = 0 | xB = 0 | ||
xC = 0 | xC = 0 | ||
y.hat <- predict( | y.hat <- predict(model_stability, data.frame(A = xA, B = xB, C = xC)) | ||
paste0('Predicted stability is: ', y.hat, ' days.') | paste0('Predicted stability is: ', y.hat, ' days.') | ||
</code> | </code> | ||
</div></html> | </div></html> | ||
Revision as of 14:40, 2 October 2019
Part 1
Your family runs a small business selling products online. The first factor of interest is whether to provide free shipping over €30 or over €50. The second factor is whether or not the purchaser must first create a profile before completing the transaction. The purchaser can still complete their transaction without creating a profile. Below are the data collected, showing the 8 experiments.
Part 2
Continuing with the case above:
Part 3
Your group is developing a new product, but have been struggling to get the product’s stability, measured in days, to the level required. You are aiming for a stability value of 50 days or more.