REVIEW 2 major objections 1 minor 29 references
MBRarefy: data-adaptive multi-bin rarefying for alpha diversity association analysis
T0 review · 2 major / 1 minor · reviewed 2026-06-26 · grok-4.3
Pith's one-line read A genetic algorithm automates selection of library size bin thresholds for multi-bin rarefying in alpha diversity analysis.
desk verdict MBRarefy is an R package that automates bin threshold choice for multi-bin rarefying via genetic algorithm, but supplies no validation that the automation improves results. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
Genetic algorithm that optimizes library size bin thresholds based on rarefying-derived profiles, replacing manual choices with data-driven selection.
What would settle it
Run association tests on simulated count data with known true effects and varying library sizes, then compare power and false positive rates between GA-selected bins and fixed ad hoc thresholds.
Extended reading notes
Core claim
MBRarefy provides automated, data-adaptive selection of library size bin thresholds via a genetic algorithm that replaces ad hoc cutpoints with an objective optimization procedure based on the rarefying-derived profiles, supporting repeated rarefying, bin-wise testing, and cross-bin meta-analysis for alpha diversity association analysis.
Load-bearing premise
The genetic algorithm optimization based on rarefying-derived profiles yields bin thresholds that produce statistically valid or more powerful association results than ad hoc choices.
Editorial extensions
If this is right
- Replaces ad hoc cutpoints with objective optimization for bin thresholds.
- Supports repeated rarefying within bins followed by bin-wise testing and cross-bin meta-analysis.
- Enables a full reproducible pipeline from raw count files to combined inferential results.
- Includes file-based sample-wise processing and standardized output generation.
Reading between the lines
- Wider use could reduce variability in results that currently stems from different researchers choosing different manual bins.
- The same GA approach might apply to other count-based association tasks where library size variation confounds the signal.
- Direct comparison of GA outputs against alternative bin-selection heuristics on real datasets would quantify practical gains.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript presents MBRarefy, an R package implementing a multi-bin rarefying workflow for alpha diversity association analysis under heterogeneous library sizes. Building on Li et al. (2024), it adds automated, data-adaptive selection of library-size bin thresholds via a genetic algorithm (GA) that optimizes based on rarefying-derived profiles, plus file-based sample processing and standardized output generation to support the full pipeline from raw counts to meta-analysis results.
Significance. If the GA-based bin selection demonstrably improves reproducibility or statistical performance over ad hoc thresholds, the package would provide a useful, reproducible tool for microbiome association studies; the work is primarily a software contribution rather than a new statistical derivation.
major comments (2)
- [Abstract] Abstract: the central claim that the GA supplies an 'objective optimization procedure' replacing ad hoc cutpoints is presented without any simulation results, real-data benchmarks, or error analysis comparing GA-derived thresholds to manual choices on metrics such as type-I error, power, or stability of association p-values; this validation is load-bearing for the advertised new feature.
- [Methods (GA description)] No section or table supplies quantitative evidence (e.g., simulation settings, GA fitness function definition, or cross-validation of selected bins) that the optimization based on rarefying-derived profiles yields statistically valid or more powerful results; the manuscript therefore rests on an untested assumption about the GA's inferential benefit.
minor comments (1)
- [Availability] The availability statement points to a GitHub repository; the manuscript should include a permanent archive link (e.g., Zenodo DOI) and a brief description of the package's test suite or example workflow.
Simulated Author's Rebuttal
Thank you for the opportunity to respond to the referee's comments. We appreciate the recognition of MBRarefy as a software contribution and agree that the genetic algorithm (GA) feature requires empirical validation to support claims of objective optimization. We will revise the manuscript to address these points.
read point-by-point responses
-
Referee: [Abstract] Abstract: the central claim that the GA supplies an 'objective optimization procedure' replacing ad hoc cutpoints is presented without any simulation results, real-data benchmarks, or error analysis comparing GA-derived thresholds to manual choices on metrics such as type-I error, power, or stability of association p-values; this validation is load-bearing for the advertised new feature.
Authors: We agree that the abstract's claim requires supporting evidence. In the revised version we will add simulation results and real-data benchmarks (including type-I error, power, and p-value stability) comparing GA-derived thresholds to ad hoc choices, and we will update the abstract to reflect these findings. revision: yes
-
Referee: [Methods (GA description)] No section or table supplies quantitative evidence (e.g., simulation settings, GA fitness function definition, or cross-validation of selected bins) that the optimization based on rarefying-derived profiles yields statistically valid or more powerful results; the manuscript therefore rests on an untested assumption about the GA's inferential benefit.
Authors: We concur that the Methods section currently lacks this quantitative evidence. The revision will include an explicit definition of the GA fitness function, full simulation settings, cross-validation details for bin selection, and a new table or figure reporting performance metrics to demonstrate statistical validity and any power gains. revision: yes
Circularity Check
No significant circularity
full rationale
The manuscript describes an R software package that implements an existing multi-bin rarefying workflow (explicitly credited to Li et al. 2024) and adds a genetic-algorithm routine for choosing bin thresholds. No equations, derivations, or statistical predictions are presented whose outputs are definitionally identical to their inputs; the GA step is an optimization heuristic applied to rarefying profiles, not a fitted parameter re-labeled as a prediction. The single self-citation supplies the base method rather than serving as the sole justification for any uniqueness claim or ansatz. The paper therefore contains no load-bearing circular steps of the enumerated kinds.
Assumptions & free parameters
Cite this review
Pith. "Pith review of MBRarefy: data-adaptive multi-bin rarefying for alpha diversity association analysis." pith.science (2026). https://pith.science/paper/NR3RJUWO
@misc{pith2026260621000,
author = {Pith},
title = {Pith review of: MBRarefy: data-adaptive multi-bin rarefying for alpha diversity association analysis},
year = {2026},
howpublished = {\url{https://pith.science/paper/NR3RJUWO}},
note = {Machine review of arXiv:2606.21000}
}
read the original abstract
Summary: This paper presents MBRarefy, an R package that provides a reproducible workflow for alpha diversity analysis under confounding from heterogeneous library sizes. Building on the multi-bin rarefying approach in Li et al (2024), MBRarefy supports alpha diversity association analysis with repeated rarefying, bin-wise testing, and cross-bin meta-analysis. A key new feature is automated, data-adaptive selection of library size bin thresholds via a genetic algorithm (GA), which replaces ad hoc cutpoints with an objective optimization procedure based on the rarefying-derived profiles. The package also supports routine data-management tasks, including file-based sample-wise processing and standardized output generation, enabling users to execute the full analysis pipeline from raw count files to combined inferential results. Availability and implementation: The R package MBRarefy is freely available on GitHub at https://github.com/mli171/MBRarefy.
Figures
Reference graph
Works this paper leans on
-
[1]
Summarizing and correcting the
Benjamini, Yuval and Speed, Terence P , journal=. Summarizing and correcting the. 2012 , publisher=
2012
-
[2]
Scientific reports , volume=
Enhancing diversity analysis by repeatedly rarefying next generation sequencing data describing microbial communities , author=. Scientific reports , volume=. 2021 , publisher=
2021
-
[3]
Bioinformatics , volume=
Associating microbiome composition with environmental covariates using generalized UniFrac distances , author=. Bioinformatics , volume=. 2012 , publisher=
2012
-
[4]
Cancer immunology research , volume=
Expansion of candidate HPV-specific T cells in the tumor microenvironment during chemoradiotherapy is prognostic in HPV16+ Cancers , author=. Cancer immunology research , volume=. 2022 , publisher=
2022
-
[5]
Nature genetics , volume=
Immunosequencing identifies signatures of cytomegalovirus exposure history and HLA-mediated effects on the T cell repertoire , author=. Nature genetics , volume=. 2017 , publisher=
2017
-
[6]
Clinical Cancer Research , volume=
T-cell receptor repertoire sequencing in the era of cancer immunotherapy , author=. Clinical Cancer Research , volume=. 2023 , publisher=
2023
-
[7]
Frontiers in microbiology , volume=
Microbiome datasets are compositional: and this is not optional , author=. Frontiers in microbiology , volume=. 2017 , publisher=
2017
-
[8]
Ecology , volume=
The nonconcept of species diversity: a critique and alternative parameters , author=. Ecology , volume=. 1971 , publisher=
1971
Show all 29 references
-
[9]
Bioinformatics , volume=
A rarefaction-without-resampling extension of PERMANOVA for testing presence--absence associations in the microbiome , author=. Bioinformatics , volume=. 2022 , publisher=
2022
-
[10]
Current diabetes reports , volume=
T cell receptor profiling in type 1 diabetes , author=. Current diabetes reports , volume=. 2017 , publisher=
2017
-
[11]
Frontiers in microbiology , volume=
The power of microbiome studies: some considerations on which alpha and beta metrics to use and how to report results , author=. Frontiers in microbiology , volume=. 2022 , publisher=
2022
-
[12]
PLoS One , volume=
T cell receptor repertoire among women who cleared and failed to clear cervical human papillomavirus infection: An exploratory proof-of-principle study , author=. PLoS One , volume=. 2018 , publisher=
2018
-
[13]
Journal of the American Statistical Association , volume=
Cauchy combination test: a powerful test with analytic p-value calculation under arbitrary dependency structures , author=. Journal of the American Statistical Association , volume=. 2020 , publisher=
2020
-
[14]
The American Statistician , volume=
The Cauchy combination test under arbitrary dependence structures , author=. The American Statistician , volume=. 2023 , publisher=
2023
-
[15]
Bioinformatics , volume=
A multi-bin rarefying method for evaluating alpha diversities in TCR sequencing data , author=. Bioinformatics , volume=. 2024 , publisher=
2024
-
[16]
changepoint
Li, Mo and Lu, QiQi , journal=. changepoint
-
[17]
Li, Mo and Lu, QiQi and Lund, Robert and Shi, Xueheng , journal=
-
[18]
2025 , note =
microbiomeDataSets: Experiment Hub based microbiome datasets , author =. 2025 , note =
2025
-
[19]
BMC biology , volume=
A comprehensive evaluation of diversity measures for TCR repertoire profiling , author=. BMC biology , volume=. 2025 , publisher=
2025
-
[20]
Methods in Ecology and Evolution , volume=
Methods for normalizing microbiome data: an ecological perspective , author=. Methods in Ecology and Evolution , volume=. 2019 , publisher=
2019
-
[21]
PLoS computational biology , volume=
Waste not, want not: why rarefying microbiome data is inadmissible , author=. PLoS computational biology , volume=. 2014 , publisher=
2014
-
[22]
Nature communications , volume=
Comprehensive T cell repertoire characterization of non-small cell lung cancer , author=. Nature communications , volume=. 2020 , publisher=
2020
-
[23]
Oikos , volume=
A conceptual guide to measuring species diversity , author=. Oikos , volume=. 2021 , publisher=
2021
-
[24]
Biometrika , volume=
Combining p-values via averaging , author=. Biometrika , volume=. 2020 , publisher=
2020
-
[25]
Microbiome , volume=
Normalization and microbial differential abundance strategies depend upon data characteristics , author=. Microbiome , volume=. 2017 , publisher=
2017
-
[26]
Frontiers in microbiology , volume=
Rarefaction, alpha diversity, and statistics , author=. Frontiers in microbiology , volume=. 2019 , publisher=
2019
-
[27]
Proceedings of the National Academy of Sciences , volume=
The harmonic mean p-value for combining dependent tests , author=. Proceedings of the National Academy of Sciences , volume=. 2019 , publisher=
2019
-
[28]
2018 , publisher=
Statistical analysis of microbiome data with R , author=. 2018 , publisher=
2018
-
[29]
Cancer Immunology, Immunotherapy , volume=
Characterization of T cell receptor repertoire in penile cancer , author=. Cancer Immunology, Immunotherapy , volume=. 2024 , publisher=
2024
Reviewed June 26, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.