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When Are Random Data Not Random, or Is the PTP Test Useful?

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Summary
This summary is machine-generated.

The permutation tail probability (PTP) test shows very low power for detecting character covariation in phylogenetic data. Simulation studies are recommended for evaluating statistical tools in phylogenetics.

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Area of Science:

  • Phylogenetics
  • Statistical analysis
  • Evolutionary biology

Background:

  • The permutation tail probability (PTP) test is used to assess character covariance in phylogenetic data.
  • Previous studies indicated low discriminatory power of the PTP test using bootstrap measures.

Purpose of the Study:

  • To statistically evaluate the performance of the PTP test in detecting character covariation.
  • To investigate the factors influencing the PTP test's performance.

Main Methods:

  • Application of an appropriate statistical approach to analyze PTP test performance.
  • Examination of PTP test dependency on the number of terminals and character states.

Main Results:

  • The PTP test demonstrates extreme weakness in detecting the absence of character covariation.
  • PTP test performance is highly sensitive to the number of terminals and proportion of character states in phylogenetic matrices.

Conclusions:

  • The PTP test is unreliable for assessing character covariation in phylogenetic analyses.
  • Simulation studies are advocated for robustly testing statistical tools in phylogenetics.