MANE 6313
Week 5, Module B
Student Learning Outcome
Analyze simple comparative experiments and experiments with a single factor.
Module Learning Outcome
Preparing data from a randomized complete block design in R.
Problem 4.8 (9th Edition Textbook)
Problem 4.8 - Spreadsheet
Data Preparation
Three different approaches:
- Microsoft Excel Spreadsheet
- R code
- agricolae package
Model Data Requirements
-
Models will have form of response~factor1+factor2 for a randomized block design
-
Response variable must be numeric
- All factor variables must be of type factor or character
Spreadsheet Approach
Spreadsheet Approach, part 2
- Watch carefully the variable declarations when importing Excel Spreadsheets
- readxl will try to import all variables as numeric if possible
-
Can cause problems in aov() command
-
Change factors from numeric to character when importing or
- add as.factor(var) or factor(var) in the model statement for numerica data
R Approach
agricolae Package
- Tools to build data frames for all of the experiments in Chapter 4 with randomized run order
- May be (or will be) difficult to use with homework problems
- Will be discussed in detail in Module C