Hi Knime Forum

I am trying to use the Paired t-test node (under Statistics) to run on uneven sample sizes. My data looks like the following (the numbers are made up)

Sample 1 |
Sample 2 |

34.5 |
? |

52.4 |
? |

44.3 |
? |

? |
8.4 |

? |
9.2 |

? |
7.4 |

? |
5.4 |

? |
8.4 |

? |
7.2 |

? |
7.8 |

KNIME gives me the following "Execute failed: degrees of freedom (-1)"

I understand that using uneven sample sizes in a t-test requires a little more work than a equal sample size, is KNIME unable to handle this? Should I look into using an R script here? Thank you for the help.

Dennis

Quick update,

I tried some test data in the following format and the T-test worked ok (I import the data via file)

Sample 1 |
Sample 2 |

34.5 |
8.4 |

52.4 |
9.2 |

44.3 |
7.4 |

? |
5.4 |

? |
8.4 |

? |
7.2 |

? |
7.8 |

The first post the data was generate in KNIME via two different methods and then "concatentated". Is there a good way to convert the data in the initial post to how it looks in this post?

Thank you

Dennis

Ok I can answer my own question...hopefully down the road someone will find this useful.

Rather than concatentate this data after processing, I process all the data upfront and then Pivot the output with each sample generating a LIST in the aggregation method. I then use an Ungroup node to generate data as above.

Dennis