Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

The Mantel-Cox Log-Rank Test01:19

The Mantel-Cox Log-Rank Test

1.0K
The Mantel-Cox log-rank test is a widely used statistical method for comparing the survival distributions of two groups. It tests whether a statistically significant difference exists in survival times between the groups without assuming a specific distribution for the survival data, making it a non-parametric test. This flexibility makes the log-rank test particularly valuable in medical research and other fields where the timing of an event, such as death or disease recurrence, is of...
1.0K
Odds Ratio01:09

Odds Ratio

1.8K
The odds ratio (OR) is a statistical measure used extensively in epidemiology and research to quantify the strength of association between exposure and outcome across different groups. Unlike relative risk, which compares the probabilities of an event occurring, the odds ratio compares the odds of an event occurring in the exposed group to the odds of it occurring in the unexposed group. The odds, in this context, are calculated as the probability of the event happening divided by the...
1.8K
Poisson's Ratio01:23

Poisson's Ratio

1.1K
Poisson's ratio is a material property that indicates their stress response. It explains the connection between the elongation or compression a material undergoes in the direction of an applied force and the contraction or expansion it experiences perpendicular to that force. When a slender bar is loaded axially, it stretches in the direction of the force and contracts laterally. Poisson's ratio is the negative ratio of this lateral contraction to the axial elongation. The negative sign...
1.1K
Hazard Ratio01:12

Hazard Ratio

597
The hazard ratio (HR) is a widely used measure in clinical trials to compare the risk of events, such as death or disease recurrence, between two groups over time. It reflects the ratio of hazard rates—the instantaneous risk of the event occurring—between a treatment group and a control group. This measure provides valuable insights into the relative effectiveness of a treatment by assessing how the risk of an event differs between the two groups.
For example, in a clinical trial...
597
The Ratio of X Chromosome to Autosomes02:45

The Ratio of X Chromosome to Autosomes

9.5K
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.  
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
9.5K
Transformers with Off-Nominal Turns Ratios01:25

Transformers with Off-Nominal Turns Ratios

526
In scenarios involving parallel transformers with disparate ratings, developing per-unit models requires accommodating off-nominal turns ratios. This situation arises when the selected base voltages are not proportional to the transformer’s voltage ratings. Consider a transformer where the rated voltages are related by the term a. If the chosen voltage bases satisfy a relationship involving term b, term c is defined as the ratio of these bases. This ratio is then substituted into the...
526

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The Sensory and Physicochemical Properties of Honeybush Tea Depend on the Brewing Water: A Preliminary Study.

Journal of food science·2025
Same author

The potential of red-fleshed apples for cider production.

Comprehensive reviews in food science and food safety·2025
Same author

Autophagy-induced cell death by aqueous and polyphenol-enriched extracts of honeybush (<i>Cyclopia</i> spp.) in liver and colon cancer cells.

Food science & nutrition·2024
Same author

Anti-allergic effect of <i>Cyclopia</i> (honeybush) extracts via anti-degranulation activity in a murine allergy model for inhaled antigen.

Bioscience of microbiota, food and health·2024
Same author

Development of sensory tools for green rooibos (Aspalathus linearis (Burm.f.) R.Dahlgren) and changes in quality attributes during shelf-life storage.

Journal of the science of food and agriculture·2024
Same author

Food-grade phytosome vesicles for nanoencapsulation of labile <i>C</i>-glucosylated xanthones and dihydrochalcones present in a plant extract matrix-Effect of process conditions and stability assessment.

Food science & nutrition·2023
Same journal

Smartphone-assisted fluorescence and colorimetric dual-mode sensor for visual quantitative detection of nitrite and nitrate in real samples.

Analytica chimica acta·2026
Same journal

Folding integrated all-paper photoelectrochemical immunoassay using annealed ZnO for point-of-care detection of ferritin.

Analytica chimica acta·2026
Same journal

Dual-mode electrochemical-SERS detection of chloramphenicol based on dual-signal enhancement.

Analytica chimica acta·2026
Same journal

Multi-screening of beta-lactam antibiotics in milk based on Fe<sub>3</sub>O<sub>4</sub>@phage/bacteria system and aggregation induced emission luminogen.

Analytica chimica acta·2026
Same journal

A porous phosphate-rich β-cyclodextrin polymer for efficient and broad-spectrum enrichment of antibiotics.

Analytica chimica acta·2026
Same journal

Corrigendum to "LUMIN: A novel algorithm for automated mixture quantification using 1D <sup>1</sup>H NMR spectra" [Analytica Chimica Acta 1411 (2026) 345639].

Analytica chimica acta·2026
See all related articles

Related Experiment Video

Updated: Jan 27, 2026

A New Straightforward Method for Lipophilicity logP Measurement using 19F NMR Spectroscopy
09:32

A New Straightforward Method for Lipophilicity logP Measurement using 19F NMR Spectroscopy

Published on: January 30, 2019

15.1K

Working with log-ratios.

Zuzanna Malyjurek1, Dalene de Beer2, Elizabeth Joubert2

  • 1Institute of Chemistry, University of Silesia, 40-007, Katowice, Szkolna 9, Poland.

Analytica Chimica Acta
|March 17, 2019
PubMed
Summary
This summary is machine-generated.

Data normalization is crucial for comparing instrumental signals. Log-ratio methods like pairwise log-ratio (plr) and centered log-ratio (clr) were evaluated, with clr recommended against for biomarker identification due to signal distortion.

Keywords:
Biomarkers identificationNormalizationPairwise log-ratioPre-processingSize effect

More Related Videos

Modeling Verbal Behavior Deficits with the Stimulus Control Ratio Equation, SCoRE
06:57

Modeling Verbal Behavior Deficits with the Stimulus Control Ratio Equation, SCoRE

Published on: May 14, 2019

10.9K
Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium
13:34

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

Published on: July 8, 2015

9.5K

Related Experiment Videos

Last Updated: Jan 27, 2026

A New Straightforward Method for Lipophilicity logP Measurement using 19F NMR Spectroscopy
09:32

A New Straightforward Method for Lipophilicity logP Measurement using 19F NMR Spectroscopy

Published on: January 30, 2019

15.1K
Modeling Verbal Behavior Deficits with the Stimulus Control Ratio Equation, SCoRE
06:57

Modeling Verbal Behavior Deficits with the Stimulus Control Ratio Equation, SCoRE

Published on: May 14, 2019

10.9K
Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium
13:34

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

Published on: July 8, 2015

9.5K

Area of Science:

  • Chemometrics
  • Bioinformatics
  • Data Analysis

Background:

  • Direct comparison of instrumental signals is hindered by unknown sample concentrations.
  • Data normalization is essential to mitigate concentration-dependent 'size effects' before analysis.
  • The selection of normalization techniques significantly impacts data analysis outcomes, particularly biomarker discovery.

Purpose of the Study:

  • To evaluate the performance of log-ratio data normalization methods.
  • To compare pairwise log-ratio (plr) and centered log-ratio (clr) techniques.
  • To assess the suitability of these methods for biomarker identification.

Main Methods:

  • Application of pairwise log-ratio (plr) and centered log-ratio (clr) methods.
  • Analysis of both real and simulated datasets with varying characteristics.
  • Investigation of the impact of normalization on signal distribution and local differences.

Main Results:

  • The centered log-ratio (clr) method can distort local differences across the entire signal.
  • Pairwise log-ratio (plr) demonstrated a more reliable approach for preserving local signal information.
  • Data characteristics influenced the performance and interpretation of both log-ratio methods.

Conclusions:

  • The centered log-ratio (clr) method should be avoided for biomarker identification studies.
  • Pairwise log-ratio (plr) is a potentially more robust method for analyzing compositional data where biomarker discovery is the goal.
  • Careful consideration of normalization methods is critical for accurate biomarker identification from instrumental data.