Complete the following steps to specify the columns of data that you want to analyze.

- In Responses, enter the columns of numeric data that you want to explain or predict with the factors. If you enter more than one response, Minitab fits a separate model for each response. The response is also called the Y variable.
- In Random factors (required) enter the columns that contain group classifications for the random factors. For more information on the difference between random factors and fixed factors, go to What is the difference between fixed and random factors?.
- In Fixed factors, enter the columns that contain group classifications for the fixed factors.
- In Covariates, enter the columns that contain continuous variables that may explain or predict changes in the response.

In this worksheet Yield is the response and contains the yield taken from each alfalfa plant. Field is a random factor and indicates where the alfalfa plant grows. Field is a random factor because the fields in the data represent a random selection from a much larger number of fields that could be in the study. Variety is a fixed factor that represents six different alfalfa plants. Days is a covariate that the data collectors track but allow to vary naturally. Days represents the number of days the plant grew until it was ready to be harvested.

C1 | C2 | C3 | C4 |
---|---|---|---|

Yield | Variety | Field | Days |

3.22 | 1 | 1 | 55 |

2.29 | 2 | 2 | 58 |

3.06 | 3 | 1 | 52 |

2.78 | 4 | 2 | 61 |

… | … | … | … |