scholarly journals How to determine the statistical significance of trends in seasonal records: application to Antarctic temperatures

2021 ◽  
Author(s):  
Armin Bunde ◽  
Josef Ludescher ◽  
Hans Joachim Schellnhuber
Keyword(s):  
Multiple Testing ◽  
Statistical Significance ◽  
Climate Science ◽  
Seasonal Temperature ◽  
Multiple Testing Correction ◽  
Significance Level ◽  
Persistent Data ◽  
Short And Long Term ◽  
False Discoveries

AbstractWe consider trends in the m seasonal subrecords of a record. To determine the statistical significance of the m trends, one usually determines the p value of each season either numerically or analytically and compares it with a significance level $${{\tilde{\alpha }}}$$ α ~ . We show in great detail for short- and long-term persistent records that this procedure, which is standard in climate science, is inadequate since it produces too many false positives (false discoveries). We specify, on the basis of the family wise error rate and by adapting ideas from multiple testing correction approaches, how the procedure must be changed to obtain more suitable significance criteria for the m trends. Our analysis is valid for data with all kinds of persistence. Specifically for long-term persistent data, we derive simple analytical expressions for the quantities of interest, which allow to determine easily the statistical significance of a trend in a seasonal record. As an application, we focus on 17 Antarctic station data. We show that only four trends in the seasonal temperature data are outside the bounds of natural variability, in marked contrast to earlier conclusions.

أثر محددات الاستثمار في الاقتصاد العراقي للمدة (2004-2018) ، دراسة قياسية

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
مهند المحمدي ◽  
محمد الحياني
Keyword(s):  
Error Correction ◽  
Statistical Significance ◽  
Economic Thought ◽  
Explanatory Variables ◽  
Equilibrium Relationship ◽  
Cointegration Tests ◽  
Short And Long Term ◽  
Standard Models ◽  
Theoretical Foundations

The research aims to measure and analyze the determinants of investment in the Iraqi economy and study the theoretical foundations of investment and analyze the viewpoint of the most important schools of economic thought regarding investment and investment determinants and their effects on economic activity , and by using possible standard models as the results of standard analysis using the joint integration tests of time series . cointegration tests, they have proven the existence of a long-term equilibrium relationship according to the methodology of the results of estimating the short and long-term parameters and the error correction parameter(ECM) , it is moving from a set of explanatory variables towards The dependent variable, while the value of the error correction vector coefficient was negative and significant , as it reached (-0.59%) , which means the fulfillment of the two basic conditions in this parameter , namely : its negative value and the statistical significance . This means that (0.59) of the short-term errors are automatically corrected during the unit of time (year) to reach the equilibrium in the long term, meaning that the investment requires about less then a year (1.6) , that is , approximately a year and 6 days to reach its equilibrium value in the long term , In other words , the previous period deviates from the long-term equilibrium and is corrected in the current by (59%) . This indicates that the adjustment in the model was relatively fast .

scholarly journals Radiofrequency ablation versus traditional liver resection and chemotherapy for liver metastases from gastric cancer

2020 ◽  
Vol 48 (7) ◽  
pp. 030006052094050
Author(s):  
Kezhong Tang ◽  
Bo Zhang ◽  
Linping Dong ◽  
Lantian Wang ◽  
Zhe Tang
Keyword(s):  
Gastric Cancer ◽  
Radiofrequency Ablation ◽  
Liver Resection ◽  
Liver Metastasis ◽  
Liver Metastases ◽  
Statistical Significance ◽  
Local Treatment ◽  
Long Term Outcomes ◽  
Short And Long Term

Objective To compare the short- and long-term outcomes of radiofrequency ablation (RFA) versus liver resection and chemotherapy for liver metastases from gastric cancer. Methods We retrospectively evaluated 50 patients who underwent curative gastrectomy and local treatments for liver metastases (RFA, n = 20; liver resection, n = 20; and chemotherapy, n = 10) from 2008 to 2018. Results The short- and long-term outcomes of each local treatment were evaluated. The median overall survival (OS) after RFA was similar to that after liver resection (20 vs. 20 months, respectively) and longer than that after chemotherapy (20 vs. 10 months, respectively). The 3-year OS and progression-free survival (PFS) rates after RFA were 20% and 10%, respectively, while those in the liver resection group were 23.5% and 23.5%, respectively. The 3-year OS rate after chemotherapy was 10%. The size and number of metastases were prognostic factors for patients with gastric cancer with liver metastasis without statistical significance. Conclusions Among patients with liver metastasis from gastric cancer, OS and PFS were satisfactory and comparable between RFA and liver resection but better than those of chemotherapy. RFA is an appropriate option for patients with gastric cancer who have a solitary liver metastasis measuring ≤3.0 cm.

Health economics using feature selection algorithm and regression method for prediction of ending cash

2019 ◽  
Vol 14 ◽  
Author(s):  
Zinat Ansari
Keyword(s):  
Feature Selection ◽  
Health Economics ◽  
Feature Selection Method ◽  
Selection Algorithm ◽  
Feature Selection Algorithm ◽  
Significance Level ◽  
Short And Long Term ◽  
Attribute Evaluation ◽  
Interest Payments

Background: Health economics are amongst academic fields which can aid in ameliorating conditions so as to perform better decisions in regards to the economy such as determining cash prices. The prediction of ending cash is fundamental for internal and external users and can come quite handy in terms of health economics. The most important purpose of financial reporting is the presentation of information to predict ending cash. Ergo, the aim of the research is to predict ending cash value using feature selection and MLR method from 2010-2012. Methods: A feature selection algorithm (Best-First, Greedy-Stepwise and Ranker) was employed in this research to nominate relevant data that affect ending cash. Results: Based on the results of the deployed feature selection method, the following features were indicated as the most relevant in terms of determine ending cash: interest payments for loans, dividends received from short and long term deposits, total net flow of investment activities, net increase (decrease) in cash and beginning cash based on best-first (CFS-Subset-Evaluation) and Greedy-Stepwise (CFS-Subset-Evaluation). Net out flow, dividends, dividends paid, interest payments for loans and dividends received deposits for short and long term were the most important data as indicated by the Ranker (Info-Gain-Attribute-Evaluation, Gain-Ratio-Attribute-Evaluation and Symmetricer-Attribute-Evaluation). According to Ranker (Principal-Components and Relifef-FAttribute-Evaluation) the best data for determining ending cash include beginning cash, interest payments for loans, dividends, net increase (decrease) in cash and dividends received from short and long term deposits. The findings were also indicative of a positive and highly significant correlation between dividends received from short and long term deposits and beginning cash (1.00**), with a significance level of 0.01, whereas the observed correlation between interest payments for loans and ending cash (0.999**), at a significance level of 0.01 was negatively significant. Conclusions: The present research attempted to reduce the volume of data required for predicting end cash by means of employing a feature selection so as to save both precious money and time.

scholarly journals Statistical significance of seasonal warming/cooling trends

2017 ◽  
Vol 114 (15) ◽  
pp. E2998-E3003 ◽  
Author(s):  
Josef Ludescher ◽  
Armin Bunde ◽  
Hans Joachim Schellnhuber
Keyword(s):  
Multiple Testing ◽  
Short Term Memory ◽  
Statistical Significance ◽  
Gaussian White Noise ◽  
Long Term Memory ◽  
Climate Trends ◽  
Climate Trend ◽  
Term Memory ◽  
Seasonal Climate

The question whether a seasonal climate trend (e.g., the increase of summer temperatures in Antarctica in the last decades) is of anthropogenic or natural origin is of great importance for mitigation and adaption measures alike. The conventional significance analysis assumes that (i) the seasonal climate trends can be quantified by linear regression, (ii) the different seasonal records can be treated as independent records, and (iii) the persistence in each of these seasonal records can be characterized by short-term memory described by an autoregressive process of first order. Here we show that assumption ii is not valid, due to strong intraannual correlations by which different seasons are correlated. We also show that, even in the absence of correlations, for Gaussian white noise, the conventional analysis leads to a strong overestimation of the significance of the seasonal trends, because multiple testing has not been taken into account. In addition, when the data exhibit long-term memory (which is the case in most climate records), assumption iii leads to a further overestimation of the trend significance. Combining Monte Carlo simulations with the Holm–Bonferroni method, we demonstrate how to obtain reliable estimates of the significance of the seasonal climate trends in long-term correlated records. For an illustration, we apply our method to representative temperature records from West Antarctica, which is one of the fastest-warming places on Earth and belongs to the crucial tipping elements in the Earth system.

scholarly journals POEAS: Automated Plant Phenomic Analysis Using Plant Ontology

2014 ◽  
Vol 8 ◽  
pp. BBI.S19057 ◽  
Author(s):  
Khader Shameer ◽  
Mahantesha Bn Naika ◽  
Oommen K. Mathew ◽  
Ramanathan Sowdhamini
Keyword(s):  
Multiple Testing ◽  
Large Scale ◽  
Statistical Significance ◽  
Enrichment Analysis ◽  
Multiple Testing Correction ◽  
Background Population ◽  
Complementary Resource ◽  
Plant Ontology ◽  
Plant Genes ◽  
Cellular Components

Biological enrichment analysis using gene ontology (GO) provides a global overview of the functional role of genes or proteins identified from large-scale genomic or proteomic experiments. Phenomic enrichment analysis of gene lists can provide an important layer of information as well as cellular components, molecular functions, and biological processes associated with gene lists. Plant phenomic enrichment analysis will be useful for performing new experiments to better understand plant systems and for the interpretation of gene or proteins identified from high-throughput experiments. Plant ontology (PO) is a compendium of terms to define the diverse phenotypic characteristics of plant species, including plant anatomy, morphology, and development stages. Adoption of this highly useful ontology is limited, when compared to GO, because of the lack of user-friendly tools that enable the use of PO for statistical enrichment analysis. To address this challenge, we introduce Plant Ontology Enrichment Analysis Server (POEAS) in the public domain. POEAS uses a simple list of genes as input data and performs enrichment analysis using Ontologizer 2.0 to provide results in two levels, enrichment results and visualization utilities, to generate ontological graphs that are of publication quality. POEAS also offers interactive options to identify user-defined background population sets, various multiple-testing correction methods, different enrichment calculation methods, and resampling tests to improve statistical significance. The availability of such a tool to perform phenomic enrichment analyses using plant genes as a complementary resource will permit the adoption of PO-based phenomic analysis as part of analytical workflows. POEAS can be accessed using the URL http://caps.ncbs.res.in/poeas .

scholarly journals Statistical Uncertainty in Hydrometeorological Trend Analyses

2016 ◽  
Vol 2016 ◽  
pp. 1-26 ◽  
Author(s):  
Charles Onyutha
Keyword(s):  
Linear Trend ◽  
Theoretical Understanding ◽  
Significance Level ◽  
Trend Analyses ◽  
Comprehensive Information ◽  
Cyclical Component ◽  
Resampling Procedure ◽  
Rank Difference ◽  
Short And Long Term

This study demonstrates the existence of uncertainty in hydrometeorological trend analyses using historical rainfall from Kenya in East Africa. With respect to the influence of short- and long-term persistence on trend analyses, a total of 13 approaches of rank-based techniques including Mann-Kendall, Spearman’s Rho, and Cumulative Rank Difference (CRD) tests were employed. Graphically, CRD-based diagnoses of trends and subtrends were performed. To assess data-related uncertainty, a resampling procedure was applied. It was shown that at a selected significance level, the null hypothesisH0(no trend) can be rejected for trend direction while the evidence to rejectH0(zero trend magnitude) is statistically insufficient. Graphical and statistical approaches when combined yield more influential and comprehensive information for inference than relying purely on statistical results. Alongside an apparent linear trend, variations in the nonlinear (e.g., cyclical) component of the series may also not be due to natural randomness. Method-related uncertainty is not negligible especially for series with persistent fluctuations. These findings shed light on the need to assess uncertainty on trend results. Furthermore, it is recommended that the conclusiveness of trends be cautiously premised not only on statistical grounds but also on more considered physical and/or theoretical understanding of the hydrometeorological processes.

scholarly journals IL7RA rs6897932 Polymorphism is Associated with Better CD4+ T-Cell Recovery in HIV Infected Patients Starting Combination Antiretroviral Therapy

Biomolecules ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 233 ◽  
Author(s):  
Resino ◽  
Navarrete-Muñoz ◽  
Blanco ◽  
Pacheco ◽  
Castro ◽  
...  
Keyword(s):  
T Cells ◽  
Antiretroviral Therapy ◽  
Cd4 T Cells ◽  
Multiple Testing ◽  
Statistical Significance ◽  
Combination Antiretroviral Therapy ◽  
Cd4 Cells ◽  
Cell Recovery ◽  
Multiple Testing Correction

Interleukin-7 receptor subunit alpha (IL7RA) rs6897932 polymorphism is related to CD4+ recovery after combination antiretroviral therapy (cART), but no studies so far have analyzed its potential impact in patients with very low CD4+ T-cells count. We aimed to analyze the association between IL7RA rs6897932 polymorphism and CD4+ T-cells count restoration in HIV-infected patients starting combination antiretroviral therapy (cART) with CD4+ T-cells count <200 cells/mm3. We performed a retrospective study in 411 patients followed for 24 months with a DNA sample available for genotyping. The change in CD4+ T-cells count during the follow-up was considered as the primary outcome. The rs6897932 polymorphism had a minimum allele frequency (MAF) >20% and was in Hardy–Weinberg equilibrium (p = 0.550). Of 411 patients, 256 carried the CC genotype, while 155 had the CT/TT genotype. The CT/TT genotype was associated with a higher slope of CD4+ T-cells recovery (arithmetic mean ratio; AMR = 1.16; p = 0.016), higher CD4+ T-cells increase (AMR = 1.19; p = 0.004), and higher CD4+ T-cells count at the end of follow-up (AMR = 1.13; p = 0.006). Besides, rs6897932 CT/TT was related to a higher odds of having a value of CD4+ T-cells at the end of follow-up ≥500 CD4+ cells/mm3 (OR = 2.44; p = 0.006). After multiple testing correction (Benjamini–Hochberg), only the increase of ≥ 400 CD4+ cells/mm3 lost statistical significance (p = 0.052). IL7RA rs6897932 CT/TT genotype was related to a better CD4+ T-cells recovery and it could be used to improve the management of HIV-infected patients starting cART with CD4+ T-cells count <200 cells/mm3.

scholarly journals Short-Term Effects of Supplemental L-Arginine, Diosmin, Troxerutin, and Hesperidin in Diabetic Patients: A Pilot Study

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Marco Bagnati ◽  
Chiara Puricelli ◽  
Giulia Bauce ◽  
Matteo Basile ◽  
Barbara Grigollo ◽  
...  
Keyword(s):  
Endothelial Dysfunction ◽  
Dietary Supplement ◽  
Statistical Significance ◽  
Cardiovascular Complications ◽  
Diabetic Patients ◽  
Significance Level ◽  
Markers Of Inflammation ◽  
Metabolic Compensation ◽  
Patients With Diabetes

Background and Aims. Inflammatory, oxidative stress, and endothelial dysfunction play a key role in the pathogenesis of long-term cardiovascular complications in patients with diabetes. The present observational prospective study is aimed at evaluating the effects of micronutrients and phytochemicals contained in the dietary supplement Flebotrofine® (AMNOL Chimica Biologica) on biochemical markers of inflammation, endothelial dysfunction, and glycemic control in patients with diabetes. Methods. 105 type 1 or type 2 diabetes patients regularly took a daily dose of the dietary supplement Flebotrofine® for three consecutive months, and haematological and biochemical parameters were checked at baseline, after three months of treatment, and one month after its suspension. Statistical comparison of the laboratory parameters was performed using the two-tailed ANOVA test for repeated samples with a statistical significance level set at p < 0.05 . Results. The daily use of Flebotrofine® did not change the glycemic metabolic compensation of enrolled patients. After three months of regular Flebotrofine® intake, the plasma levels of the antioxidant β-carotene and of arginine were significantly higher compared with the baseline values, with a decrease in the ADMA/arginine ratio. In contrast, apolipoprotein B, ApoB/ApoA1 ratio, and platelet and leukocyte counts significantly dropped. Conclusion. The daily use of Flebotrofine® might be a valid supplement of arginine, the precursor of NO, and essential in the prevention of endothelial dysfunction. The regular intake of arginine and phytochemicals also improved the antioxidant and antithrombotic profile of enrolled patients. Therefore, Flebotrofine® could be a useful dietary supplement to prevent long-term complications in patients with diabetes.

scholarly journals P347 Vedolizumab as first line biologic therapy in elderly patients with contraindications against anti-TNF therapy - A real-world nationwide cohort of patients with inflammatory bowel diseases

2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S369-S370
Author(s):  
M Attauabi ◽  
C Höglund ◽  
J Fassov ◽  
K B Pedersen ◽  
H Bansholm Hansen ◽  
...  
Keyword(s):  
Adverse Events ◽  
Elderly Patients ◽  
Clinical Remission ◽  
Biologic Therapy ◽  
Statistical Significance ◽  
Efficacy And Safety ◽  
First Line ◽  
Younger Patients ◽  
Short And Long Term

Abstract Background Data regarding the efficacy and safety of vedolizumab as the first line of biologic therapy for elderly patients with ulcerative colitis (UC) and Crohn’s disease (CD) or patients with contraindications against anti-tumor necrosis factor antagonists (anti-TNFs) are scarce. Therefore, we aimed to investigate the short and long-term efficacy and safety of vedolizumab in patients with bio-naïve UC and CD stratified according to age. Methods A Danish nationwide cohort study was conducted between November 2014 and November 2019, including all bio-naïve patients receiving vedolizumab. The primary outcomes were clinical remission, steroid-free clinical remission, and sustained clinical remission defined as clinical remission at week 14 through week 52. Elderly patients were defined as patients aged 60 years or older at initiation of vedolizumab. Results The study included 56 patients (UC: 31 (55.4%), CD: 25 (44.6%)) with 15 (60.0%) and nine (47.4%) elderly patients with UC and CD, respectively. Elderly patients with UC and CD experienced higher rates of early response, remission, and steroid-free clinical remission, which, however, did not reach statistical significance (Figures 1 and 2). However, elderly patients with CD had similar long-term response as compared with younger patients. In the overall study population, lack of remission at week 52 was associated with female gender (p=0.01) in UC and ileal CD (p=0.03). Discontinuation due to primary non-response occurred in 20.0% and 5.3%, while rates of secondary loss of response were 12.0% and 5.3% after 26 weeks and 52 weeks, respectively. Only one UC patient, who developed a serious infection, experienced a serious adverse event during treatment with vedolizumab. However, mild adverse events were experienced by 35.5% and 8.0% of patients with UC and CD, respectively. As shown in Table 1, elderly patients experienced adverse events similar to the corresponding younger patients. Conclusion Vedolizumab is effective for induction of short and long-term sustained clinical remission in bio-naïve elderly and younger UC and CD patients with contraindications to anti-TNFs.

scholarly journals The Effect of Tobacco Smoking and Smoking Cessation on Urinal miRNAs in a Pilot Study

Life ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 191
Author(s):  
Zdenka Navratilova ◽  
Stanislav Losse ◽  
Pavla Petrova ◽  
Katerina Sikorova ◽  
Alzbeta Chabronova ◽  
...  
Keyword(s):  
Smoking Cessation ◽  
Tobacco Smoking ◽  
Multiple Testing ◽  
Urine Samples ◽  
Multiple Testing Correction ◽  
Time Points ◽  
Genome Screening ◽  
Never Smokers ◽  
Short Time

The diseases associated with tobacco smoking affect miRNAs and small single-stranded non-coding RNAs. However, there are no data on urinal miRNAs in healthy smokers. We searched for the possible effect of smoking and smoking cessation on miRNA urine expression. For screening, Affymetrix miRNA 4.0 arrays were used in 33 urine samples obtained from six never smokers and from current smokers in three time-points before smoking cessation (n = 10), after short time abstinence (3–8 weeks), and after long-term abstinence (1 year). For validation, a quantitative (q) polymerase chain reaction (PCR) method was used in 93 urine samples obtained from 18 never smokers and 25 current smokers in three time-points before smoking cessation, after short time abstinence (3–8 weeks), and after long-term abstinence (1 year). In screening analysis, 5 miRNAs (hsa-miR-3620-5p, hsa-miR-3613-5p, hsa-miR-3921, hsa-miR-5094, and hsa-miR-337-3p) were dysregulated in current vs. never smokers after multiple testing corrections. Smoking cessation was accompanied by miRNA dysregulation that did not reach a significant level after a multiple testing correction. In validation analysis, three miRNAs correlated with cotinine, but they were affected neither after smoking cessation nor between current and never smokers. Our whole-genome screening of 2.578 miRNAs and validation suggest that tobacco smoking has no or only a small effect on urinal miRNAs.

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