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MANE 6313

Week 5, Module C

Student Learning Outcome

Analyze simple comparative experiments and experiments with a single factor.

Module Learning Outcome

Analyze a RCBD using R.

Problem 4.8 (9th Edition Textbook)

Graphical Analysis - Boxplot Strength~Chemical

Boxplot of strength by chemical

Boxplot Strength~Block

Boxplot of strength by block

Analysis

  • readxl() - incorrect
  • readxl() - correction 1
  • readxl() - correction 2
  • R Data
  • agricolae package

readxl Data (incorrect)

  • Notice degrees of freedom are incorrect
  • Always double check computer and make sure output makes sense

Incorrect Anova

readxl() Data, correction 1
  • Use factor() or as.factor()

readxl, correction 1

readxl() Data, correction 2

  • Change data type when importing

readxl(), correction 2

readxl() Data, correction 2

readxl() correction 2

R Data

Analysis of Variance

agricolae without randomization

  • Might be helpful with some homework problems
  • Notice how results below match problem
  • "Real" experiments should be randomized

creating rbcd

agricolae adding response

adding response to design book

agricolae with randomization

agricolae rcbd with randomization

Post Model Fitting Analysis

  • Should be continued

  • Residual analysis

  • Barrett's/Levene's test if needed
  • Multiple comparison analysis can be done on blocks but on the treatment chemical for this example!

R Demonstration