Index of papers in PLOS Comp. Biol. that mention
  • p-value
Christiaan A. de Leeuw, Joris M. Mooij, Tom Heskes, Danielle Posthuma
Analysis of CD data—gene analysis
The results of the gene analyses of the CD data are summarized in Table 2, which shows the number of significant genes at a number of different p-value thresholds.
Analysis of CD data—gene-set analysis
The comparison of competitive methods is somewhat more complicated, due to the fact that ALIGATOR, INRICH and MAGENTA all use discretization using a p-value cutoff.
Analysis of CD data—gene-set analysis
For INRICH the results are strongly dependent on the SNP p-value cutoff used, with three significant gene sets at the 0.0001 cutoff but none at the higher ones, further emphasizing the problem of choosing the correct cutoff.
Analysis of CD data—gene-set analysis
This suggests that the different methods, or methods at different p-value cutoffs, are sensitive to distinctly different kinds of gene set associations.
Analysis of summary SNP statistics
For the mean 12 statistic, a gene p-value is then obtained by using a known approximation of the sampling distribution [20,21].
Analysis of summary SNP statistics
For the top 12 statistic such an approximation is not available, and therefore an adaptive permutation procedure is used to obtain an empirical gene p-value .
Analysis of summary SNP statistics
The empirical p-value for a gene is then computed as the proportion of permuted top 12 statistics for that gene that are higher than its observed top 12 statistic.
Gene analysis
The gene analysis in MAGMA is based on a multiple linear principal components regression [18] model, using an F-test to compute the gene p-value .
Gene-set analysis
To perform the gene-set analysis, for each gene g the gene p-value pg computed with the gene analysis is converted to a Z—value 2g 2 (ID—1(1 — pg), where (ID—‘1L is the probit function.
p-value is mentioned in 17 sentences in this paper.
Topics mentioned in this paper:
Alan L. Hutchison, Mark Maienschein-Cline, Andrew H. Chiang, S. M. Ali Tabei, Herman Gudjonson, Neil Bahroos, Ravi Allada, Aaron R. Dinner
E 3 A A g Time s 'r r a E A AA Time Time
By definition, a p-value is the likelihood of obtaining a test statistic equal to or more extreme than the value that is observed if the null hypothesis is true—it increases cumulatively as one progresses through a set of rank ordered test statistics.
E 3 A A g Time s 'r r a E A AA Time Time
For a dataset generated from this null model, the p-values should be uniformly distributed from 0 to 1, exclusive: the highest Kendall’s 1‘ out of N tests should have a p-value of 1 / (N + 1), the second highest test statistic has a p-value of 2/ (N + 1), and the ith highest test statistic has a p-value of i/ (N + 1) [35].
E 3 A A g Time s 'r r a E A AA Time Time
ITK_CYCLE computes the Kendall T values for all the reference time series against the signal of interest and then performs a selection step for the lowest p-value (i.e., the highest 1‘), which we refer to here as the “initial” p-value .
Microarray metadataset
Choosing a Benjamini-Hochberg adjusted p-value cutoff of 0.05 (i.e., 5%), the number of genes and overlap between methods can be seen in Figs.
Overview
However, for large time series the ITK_CYCLE null distribution is approximately normal, allowing for a convenient, fast p-value estimate.
Simulated data benchmarks
However, this requires recomputing null distributions via MC sampling because the construction procedure introduces correlations between data points, resulting in p-value underestimates if not corrected.
p-value is mentioned in 21 sentences in this paper.
Topics mentioned in this paper:
Susan Dina Ghiassian, Jörg Menche, Albert-László Barabási
Biological validation analysis
First we identify the set of GO terms (pathways) that are significantly enriched within the given set of seed genes using Fisher’s exact test (Bonferroni corrected p-value <0.5).
DIAMOnD implementation
(2) and consequently a lower p-value .
DIAMOnD implementation
Similarly, between two proteins with the same number of connections to seeds k5, the one with lower k will result in lower p-value .
DIAMOnD implementation
Finally, we calculate the exact p-value for the remaining nodes.
Disease-gene associations
We use a genome-wide significance cutoff of p-value g 5 - 10—8.
Interaction patterns of disease proteins within the Interactome
We found that only between ~ 1%-5% of the communities detected by the different methods are significantly enriched ( p-value < 0.05, Fisher’s exact test) with any set of disease proteins (Fig.
Interaction patterns of disease proteins within the Interactome
To evaluate Whether a certain protein has more connections to seed proteins than expected under this null hypothesis, we calculate the connectivity p-value , i.e.
Interaction patterns of disease proteins within the Interactome
1H shows that the connectivity p-val-ues within the sets of known disease proteins are very significantly ( p-value < 10—241, Kolmogorov-Smirnov test) shifted towards smaller values when compared to the distributions expected for randomly scattered proteins.
The DIAMOnD algorithm
lowest p-value ) is added to the set of seed nodes, increasing their number from so —>51 2 50+1.
Validating disease modules
the number of seed genes 5 on which the p-value in Eqs.
p-value is mentioned in 10 sentences in this paper.
Topics mentioned in this paper:
Fan Yang, Evangelia Petsalaki, Thomas Rolland, David E. Hill, Marc Vidal, Frederick P. Roth
Cancer-type-specific domain mutation landscapes across 21 cancer types
We identified ~ 100 cancer-type-specific significantly mutated domain instances (SMDs) in 21 cancer types (S2 Table; P-value = 10—7, Fisher’s Exact test, False Discovery Rate (FDR) <0.05).
Cancer-type-specific domain mutation landscapes across 21 cancer types
Enrichment for Cancer Census genes was both strong and significant (~ 12-fold enrichment; P-value 2 5X 10—34, Fisher’s Exact test), and suggests the remaining 54 genes that are not already known to be cancer drivers represent good candidates.
Cancer-type-specific domain mutation landscapes across 21 cancer types
Of the 94 genes encoding cancer type-specific SMDs, 24 were found in the Sleeping Beauty dataset (~ 3-fold enrichment; P-Value 2 7X 10—06, Fisher’s Exact test).
Cancer-type-specific positioning of mutations within a given gene
These 52 genes were enriched for evidence of involvement in cancer, with 16 being Cancer Census genes (enrichment factor ~ 11.9; P-value = 6.7 X1043, Fisher’s Exact test), and 15 being candidate cancer genes according to the Sleeping Beauty screen (enrichment factor ~ 4.5; P-value = 1.9 X10'6, Fisher’s Exact test).
Cancer-type-specific significantly-mutated domain instance analyses
We chose a P-value threshold (OL = 10—7) yielding a false discovery rate (FDR) of less than 0.05.
Cancer-type-specific significantly-mutated domain instance analyses
We made a heat map representation of the hierarchical clustering of SMDs in different cancers using the “heatmap.2” R package based on the —log ( P-value ) of each cancer-type-specific domain instance.
Cancer-type-specific significantly-mutated position based mutational hotspot analyses
We calculated the mutational hotspots within each domain instance encoded by a single gene based on Fisher’s Exact test with a P-Value cutoff 0.01 (FDR <0.05).
p-value is mentioned in 8 sentences in this paper.
Topics mentioned in this paper:
Peter Klimek, Alexandra Kautzky-Willer, Anna Chmiel, Irmgard Schiller-Frühwirth, Stefan Thurner
Data
If the null hypothesis of statistical independence of these two variables cannot be rejected in a chi-squared test using a p-value of p = 0.05 the seX ratio is set to zero, SR(x,t) = O. Lead/lag indicator.
Data
The p-value for each lead and lag indicator is the probability of obtaining the observed values for I lead(d,-,x) and I lag(d,-,x) from the surrogate data.
Further comorbidities
In the enlarged sample only one out of the 123 comorbidities using the inpatient sample has a p-value greater than 0.05 (M23), all other remain significant (p<0.05).
Results/Discussion
Lead/lag behavior is identified for male and female DM1 and DMZ patients if the null hypothesis that the observed indicator values for I lead(di,x) and I lag(d,-,x) can be obtained from randomized surrogate data can be rejected with a p-value of p< 0.01.
Supporting Information
For the age groups with the smallest p-value the relative risks RR, patient ages, and the corresponding p-values are shown for DM1 and DM2, respectively.
Supporting Information
Comorbidity data for DMl patients, the relative risks RRI, the confidence intervals for RRI, if applicable the p-Value for the co-occurrence analysis, and the sex ratio for each diagnosis and age group.
Supporting Information
Comorbidity data for DM2 patients, the relative risks RRZ, the confidence intervals for RRZ, if applicable the p-Value for the co-occurrence analysis, and the sex ratio for each diagnosis and age group.
p-value is mentioned in 7 sentences in this paper.
Topics mentioned in this paper:
Daifeng Wang, Koon-Kiu Yan, Cristina Sisu, Chao Cheng, Joel Rozowsky, William Meyerson, Mark B. Gerstein
Enrichment of particular logic gates among consistent triplets by hyper-geometric test
Given a set of triplets (e.g., the triplets in Which RFl is MYC) and a particular logic gate g, we calculate a hyper-geometric enrichment p-Value to describe the enrichment of triplets consistent With the gate g as opposed to other gates as follows: The p-Value is equal kg is the number of triplets consistent With the gate g in the set, K is the total number of triplets consistent With the gate g, and N is the total number of triplets.
Loregic applications for other regulatory features
Out of these, 162 are consistent with the AND gate (with enrichment by hypergeometric test p-value <1.3*10'3), and 159 are consistent with “T 2 RH” (with enrichment by hypergeometric test p-value <7.5*10'5) making them the dominant logic gates for yeast FFL.
Loregic applications for other regulatory features
From these triplets, 446 match “T = RFZ” When RF2 is MYC (hy-pergeometric test p-value < 2.5*10'124), and 201 match “T = ~RF1+RF2” When RF1 is a miRNA and RF2 is MYC (hypergeometric test p-value < 4.1*10'25).
Validation
For example, in analyzing 871 AND-gate-consistent triplets, we found that deleting either of their TFs gave rise to substantial down-regulation of their target genes, i.e., the logarithm expression fold changes were significantly less than zero (t-test p-value = 0.068).
Validation
The two most enriched logic gates are “T = RF1” (133 triplets, hypergeometric test p-value < 4.3*10' 27) and “T = RF1+RF2 (OR)” (211 triplets, hypergeometric test p-value < 1.1*10'21)
p-value is mentioned in 5 sentences in this paper.
Topics mentioned in this paper:
Omar Al Hammal, David Alonso, Rampal S. Etienne, Stephen J. Cornell
Discussion
The power of a statistical test generally depends on three factors: first, the sample size; second, statistical significance as measured by the threshold p-value used to assess significance; and third, the effect size, which quantifies departures from the null hypothesis.
Power calculation for fixed non-neutral model parameters
For the LOGS metacommunity, and when the local dynamics are strictly neutral (7/ = 0 for model HL or c = 0 for model PC), the models are equivalent to the SNM, and the power is equal to the threshold p-value for statistical significance (0.05 in our study).
Testing the neutral null model
To calculate the p-value of our test, we compare the value of a test statistic for the test data set with values of the test statistic for data sets generated by the null model.
Testing the neutral null model
The p-value for the test is the fraction of neutral data sets Whose maximum likelihood is lower than the maximum likelihood for the test data set, i.e.
Testing the neutral null model
The neutral model is rejected if the p-value is less than the chosen threshold for statistical significance, which we take to be 0.05.
p-value is mentioned in 5 sentences in this paper.
Topics mentioned in this paper:
Giulia Menconi, Andrea Bedini, Roberto Barale, Isabella Sbrana
Insights into the functions of ORFs with peak in 3’UTR
with lowest p-value ) are identified for a range of 31 to 86 ORFs per GO term, with a mean value of 62.3 ORFs per GO term.
Statistical analysis
All enrichment Widgets list a term, a count and an associated p-Value .
Statistical analysis
The p-Value is the probability that result occurs by chance, thus a lower p-Value indicates greater enrichment Without corrections.
Statistical analysis
The p-Value is calculated using the Hypergeometric distribution.
p-value is mentioned in 4 sentences in this paper.
Topics mentioned in this paper:
Ethan S. Sokol, Sandhya Sanduja, Dexter X. Jin, Daniel H. Miller, Robert A. Mathis, Piyush B. Gupta
PEACS: Algorithm
To calculate a p-Value , a Monte Carlo sampling algorithm was implemented.
PEACS: Algorithm
The p-Value was defined as the rank of the real PEACS score in the null distribution diVided by 10,000.
Results
The empirical p-value was then determined by ranking the PEACS score for the given perturbation relative to the PEACS scores generated by this Monte Carlo procedure.
Supporting Information
Displayed are the PEACS scores, uncorrected p-Value, Bonferroni corrected p-Value , and significance (* = raw p<0.01; T = Bonfer-roni-corrected p<0.05) for genes with at least 3 knockdown conditions with 2-fold or higher knockdown.
p-value is mentioned in 4 sentences in this paper.
Topics mentioned in this paper:
William F. Flynn, Max W. Chang, Zhiqiang Tan, Glenn Oliveira, Jinyun Yuan, Jason F. Okulicz, Bruce E. Torbett, Ronald M. Levy
Pairwise covariation
Kendall's tau-b for each such pair is calculated with an accompanying Z-score from which a p-value can be calculated.
Supporting Information
PR-PR pairs ranked by Fisher exact test p-Value calculated from 2013 HIVDB sequences.
The pooled proportion PP _PS ><N5+Pf ><Nf
From these quantities, a Z-score and p-Value can be computed assuming a normal distribution using Z = (PfPs)/SE.
The pooled proportion PP _PS ><N5+Pf ><Nf
A p-Value is computed for each mutation at all 599 positions for Which the mutation is detectable in at least 5 patients Who failed therapy.
p-value is mentioned in 4 sentences in this paper.
Topics mentioned in this paper:
Ickwon Choi, Amy W. Chung, Todd J. Suscovich, Supachai Rerks-Ngarm, Punnee Pitisuttithum, Sorachai Nitayaphan, Jaranit Kaewkungwal, Robert J. O'Connell, Donald Francis, Merlin L. Robb, Nelson L. Michael, Jerome H. Kim, Galit Alter, Margaret E. Ackerman, Chris Bailey-Kellogg
Supervised learning: Classification
The coefficients give the relative importance of each feature to the predictor; associated p-values indicate the confidence in those coefficient values (a large p-value indicates an unreliable estimate of the feature contribution).
Unsupervised learning
Antibody feature:function and feature:feature correlations were computed over the set of 80 vaccinated subjects and assessed using Pearson correlation coefficient and p-value .
Unsupervised learning
For each function and each group, the feature with the largest-magnitude feature:function correlation coefficient was identified; each such feature also had the best feature:function p-value within its group, < = 0.001.
p-value is mentioned in 3 sentences in this paper.
Topics mentioned in this paper: