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**RE: 2x3 Mixed Design ANOVA**Oct 18, 2018 06:10 PM | Andrew Zalesky

RE: 2x3 Mixed Design ANOVA

Hi Ana,

I forgot that your design is a repeated measures design. If you are only interested in the group effect, a repeated measures design is not necessary. You can either run a between-group t-test for each time point or first average your data across time points and perform a single t-test of the between-group difference.

What you might be interested in testing for the current repeated measures design is the interaction between group and time. Assuming that the first 8 subjects are group 1 and the last 8 subjects are group 2, the design matrix would look like this:

1 1

2 2

4 4

1 1

2 2

4 4

1 -1

2 -2

4 -4

1 -1

2 -2

4 -4

Once again, you will need to add additional columns (one for each subject) to model within-subject effects.

I forgot that your design is a repeated measures design. If you are only interested in the group effect, a repeated measures design is not necessary. You can either run a between-group t-test for each time point or first average your data across time points and perform a single t-test of the between-group difference.

What you might be interested in testing for the current repeated measures design is the interaction between group and time. Assuming that the first 8 subjects are group 1 and the last 8 subjects are group 2, the design matrix would look like this:

1 1

2 2

4 4

1 1

2 2

4 4

1 -1

2 -2

4 -4

1 -1

2 -2

4 -4

Once again, you will need to add additional columns (one for each subject) to model within-subject effects.

*Originally posted by Ana Coelho:*Hi Dr. Zalesky,

When I add one column with the two groups encoded as 0/1, I got the warning for rank deficiency.

Why this is happening? Is related with the data or the design matrix?

Thanks in advance!

Ana

When I add one column with the two groups encoded as 0/1, I got the warning for rank deficiency.

Why this is happening? Is related with the data or the design matrix?

Thanks in advance!

Ana

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Title | Author | Date |
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Ana Coelho |
Oct 10, 2018 | |

Andrew Zalesky |
Oct 10, 2018 | |

Ana Coelho |
Oct 11, 2018 | |

Andrew Zalesky |
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Ana Coelho |
Oct 12, 2018 | |

Andrew Zalesky |
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Ana Coelho |
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Andrew Zalesky |
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Ana Coelho |
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Andrew Zalesky |
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Ana Coelho |
Mar 12, 2019 | |

Andrew Zalesky |
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Ana Coelho |
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Ana Coelho |
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Ana Coelho |
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Andrew Zalesky |
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Andrew Zalesky |
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Ana Coelho |
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Andrew Zalesky |
Oct 26, 2018 | |