scholarly journals Studying the impact of CI on pull request delivery time in open source projects—a conceptual replication

2019 ◽  
Vol 5 ◽  
pp. e245
Author(s):  
Yunfang Guo ◽  
Philipp Leitner
Keyword(s):  
Open Source ◽  
Research Question ◽  
Control Group ◽  
Delivery Time ◽  
Study Results ◽  
Speed Up ◽  
Pull Request ◽  
Bug Fixes ◽  
The Impact ◽  
Robust Evidence

Nowadays, continuous integration (CI) is indispensable in the software development process. A central promise of adopting CI is that new features or bug fixes can be delivered more quickly. A recent repository mining study by Bernardo, da Costa & Kulesza (2018) found that only about half of the investigated open source projects actually deliver pull requests (PR) faster after adopting CI, with small effect sizes. However, there are some concerns regarding the methodology used by Bernardo et al., which may potentially limit the trustworthiness of this finding. Particularly, they do not explicitly control for normal changes in the pull request delivery time during a project’s lifetime (independently of CI introduction). Hence, in our work, we conduct a conceptual replication of this study. In a first step, we replicate their study results using the same subjects and methodology. In a second step, we address the same core research question using an adapted methodology. We use a different statistical method (regression discontinuity design, RDD) that is more robust towards the confounding factor of projects potentially getting faster in delivering PRs over time naturally, and we introduce a control group of comparable projects that never applied CI. Finally, we also evaluate the generalizability of the original findings on a set of new open source projects sampled using the same methodology. We find that the results of the study by Bernardo et al. largely hold in our replication. Using RDD, we do not find robust evidence of projects getting faster at delivering PRs without CI, and we similarly do not see a speed-up in our control group that never introduced CI. Further, results obtained from a newly mined set of projects are comparable to the original findings. In conclusion, we consider the replication successful.

scholarly journals Estimating Causal Effects When the Treatment Affects All Subjects Simultaneously: An Application

2021 ◽  
Vol 5 (2) ◽  
pp. 22
Author(s):  
Chiara Binelli
Keyword(s):  
Machine Learning ◽  
Carbon Dioxide ◽  
Global Warming ◽  
Carbon Dioxide Emissions ◽  
Control Group ◽  
Sources Of Information ◽  
Average Global Temperature ◽  
Causal Impact ◽  
The Impact ◽  
Robust Evidence

Several important questions cannot be answered with the standard toolkit of causal inference since all subjects are treated for a given period and thus there is no control group. One example of this type of questions is the impact of carbon dioxide emissions on global warming. In this paper, we address this question using a machine learning method, which allows estimating causal impacts in settings when a randomized experiment is not feasible. We discuss the conditions under which this method can identify a causal impact, and we find that carbon dioxide emissions are responsible for an increase in average global temperature of about 0.3 degrees Celsius between 1961 and 2011. We offer two main contributions. First, we provide one additional application of Machine Learning to answer causal questions of policy relevance. Second, by applying a methodology that relies on few directly testable assumptions and is easy to replicate, we provide robust evidence of the man-made nature of global warming, which could reduce incentives to turn to biased sources of information that fuels climate change skepticism.

scholarly journals Hemostasis in Infertile Patients Participating in Assisted Reproduction Programmes

Doctor Ru ◽  
2021 ◽  
Vol 20 (6) ◽  
pp. 6-11
Author(s):  
A.O. Godzoeva ◽  
◽  
I.E. Zazerskaya ◽  
V.S. Vlasov ◽  
T.V. Vavilova ◽  
...  
Keyword(s):  
Reproductive Technologies ◽  
Control Group ◽  
Study Group ◽  
Study Objective ◽  
Hemostasis System ◽  
Fibrin Monomer ◽  
Study Results ◽  
Venous Thromboembolic Events ◽  
The Impact ◽  
Infertile Patients

Study Objective: To evaluate the impact of multifollicular ovarian stimulation in in vitro fertilisation (IVF) programmes on hemostasis. Study Design: perspective comparative study. Materials and Methods. The study included 68 patients divided into two groups: study group (n = 36) — infertile patients; control group (n = 32) — healthy non-pregnant women of reproductive age. The protocol with gonadotrophin releasing hormone antagonists was used for ovulation stimulation. Hemostasis system in study patients was evaluated in 2 weeks after embryos were transferred to uterus; in control group — on day 20–22 of menstrual period. For the study group, we evaluated clotting test parameters of hemostasis system, D-dimers (D-d) and fibrin monomer (FM). Study Results. We have not found statistically significant differences between hemostasis screening results of study groups. We have identified increase in pro-coagulatory properties of blood in the study group patients: increase in FM and D-d (р < 0.0001 in both cases). There is an association between study parameters and pregnancy (p < 0.001) and no association with obesity, age and infertility. Conclusion. In IVF programme, FM and D-d levels rise, evidencing hypercoagulation development. An increase in FM levels was even more significant and can be used as an early and specific fibrogenesis marker. Keywords: assisted reproductive technologies, fibrin monomer, D-dimer, hypercoagulation, venous thromboembolic events.

Can Yoga Overcome Criminality? The Impact of Yoga on Recidivism in Israeli Prisons

2020 ◽  
Vol 64 (13-14) ◽  
pp. 1461-1481
Author(s):  
Shaked Kovalsky ◽  
Badi Hasisi ◽  
Noam Haviv ◽  
Ety Elisha
Keyword(s):  
Informal Education ◽  
Matched Control ◽  
Control Group ◽  
Recidivism Rates ◽  
Matched Control Group ◽  
Rehabilitation Programs ◽  
Study Results ◽  
Alternative Practices ◽  
Criminological Theories ◽  
The Impact

In recent years, yoga practices have been integrated into formal prison rehabilitation programs of the Israel Prison Service (IPS), as part of the informal education system, giving rise to innovative criminological theories such as positive criminology that emphasize the development of offenders’ strengths by facilitating rehabilitation and reintegration processes. The purpose of the present study was to examine the correlation between yoga practice and recidivism among released prisoners who participated in yoga programs during their incarceration in comparison with a matched control group of those who did not participate in yoga programs over a follow-up period of 5 years. To examine the effectiveness of the program, propensity score matching was used to compile the comparison group from among all convicted prisoners who were released from the Israeli prisons. Study results indicate that yoga may affect recidivism, supported by a finding of lower recidivism rates among released prisoners who had practiced yoga during their incarceration, compared with a matched control group. However, further study is needed including randomized controlled trials (RCTs). In light of these positive results, we recommend policy-makers consider expanding alternative practices such as yoga into prisons, in recognition of their contribution to the rehabilitation process through the development of personal and social strengths.

The Impact of Broadband Access on Social and Economic Integration: Results from the RefugeeMobile Pilot

2019 ◽  
Author(s):  
William N Evans ◽  
Brendan Perry ◽  
Rachel Factor
Keyword(s):  
United States ◽  
Research Question ◽  
Risk Groups ◽  
The United States ◽  
Control Group ◽  
Broadband Access ◽  
Office Visits ◽  
Group Members ◽  
One Year ◽  
The Impact

Abstract The Internet is a ubiquitous feature of everyday life and an important research question is whether improving broadband access for at-risk groups such as refugees enhances social and economic outcomes. The article reports the results of the RefugeeMobile pilot where a sample of refugees to the United States were randomly assigned a smartphone (n = 82) with eight months of free service and pre-loaded apps designed to help them adjust to life in the United States, or not (n = 74). At a one-year follow-up, results indicate that assignment to treatment generates statistically significant increases in smartphone ownership and Internet access, and some measures of social integration. Results for employment and earnings were positive but statistically insignificant. Treatment-group members had fewer interactions with their case worker, a smaller fraction of in-office visits and hence a larger fraction of interactions by phone than control-group members, suggesting the pilot may have increased programme efficiency.

scholarly journals Hypoglycemic Effect of a Combined Andrographis paniculata and Caesalpinia sappan Extract in Streptozocin-Induced Diabetic Rats

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Febrika Wediasari ◽  
Gumilar A. Nugroho ◽  
Zahra Fadhilah ◽  
Berna Elya ◽  
Heri Setiawan ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Lipid Profiles ◽  
Andrographis Paniculata ◽  
Hypoglycemic Effect ◽  
Control Group ◽  
Caesalpinia Sappan ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Study Results ◽  
The Impact

Introduction. Researchers usually use herbal combinations to explore and develop traditional medicine to obtain additional benefits in the treatment of diseases, including diabetes. This study aims to evaluate the hypoglycemic effect of the combination of Andrographis paniculata (Burm. f.) Wall ex Nees and Caesalpinia sappan Linn extract (APCSE) on diabetes-induced rats. There has not been sufficient research on this combination; however, single extract studies of these plants have been widely conducted. Materials and Methods. Male Sprague Dawley rats (160–200 g) were induced by injecting a low dose of streptozotocin (35 mg/kg BW) twice and fed with a high-fat diet containing 25% fat, whereas control animals received only standard feed. Rats were treated with APCSE at doses of 100 mg and 200 mg/kg BW for seven days and compared to the APE and CSE groups treated with the extract at 100 mg, respectively. For the control group, rats were treated with metformin with a dose of 250 mg/kg. The antihyperglycemic and antihyperlipidemic effects were determined by measuring blood glucose levels and lipid profiles (cholesterol, triglycerides, HDL, and LDL). To assess the impact of the extract on pancreatic and adipose tissue, the number of pancreatic beta cells and adipocytes was evaluated through histopathological and immunohistochemical study. Results and Discussion. In a nonfasting state, the blood glucose change in APCSE 200 mg was 18.65% and was significantly lower from the DM group. However, a single extract of APE and CSE showed lower fasting blood glucose levels compared to the combined extract. Lipid profiles show no significant differences in cholesterol levels between groups; however, all treatment groups, including metformin, showed higher triglyceride levels. The APE-treated group showed significantly lower HDL and LDL, whereas CSE only showed lower LDL. The β-cell number was significantly higher after treatment with single extract CSE. The CSE and the combined extract groups showed hyperplasia adipocytes. Conclusion. The combined extract of APCSE has a moderate antihyperglycemic effect; however, a single extract may have better potential than the combined extract.

scholarly journals The Infant Cuddler Study: Evaluating the effectiveness of volunteer cuddling in infants with neonatal abstinence syndrome

2019 ◽  
Vol 25 (7) ◽  
pp. 414-418
Author(s):  
Amanda Hignell ◽  
Karen Carlyle ◽  
Catherine Bishop ◽  
Mary Murphy ◽  
Teresa Valenzano ◽  
...  
Keyword(s):  
Pilot Study ◽  
Length Of Stay ◽  
Focus Groups ◽  
Positive Impact ◽  
Surrogate Marker ◽  
Neonatal Abstinence Syndrome ◽  
Control Group ◽  
Abstinence Syndrome ◽  
Study Results ◽  
The Impact

Abstract Objectives St. Michael’s Hospital launched a volunteer cuddling program for all infants admitted into the neonatal intensive care unit in October 2015. The program utilizes trained volunteers to cuddle infants when caregivers are not available. This was a pilot study to assess the impact of a volunteer cuddle program on length of stay (LOS) and feasibility of implementation of the program. Methods A mixed methods approach was utilized to measure both quantitative and qualitative impact. A pilot cohort study with a retrospective control group assessed the feasibility of implementing a volunteer cuddling program for infants with neonatal abstinence syndrome (NAS). Length of stay was used as a surrogate marker to measure the impact of cuddling on infants being treated for Neonatal Abstinence Syndrome. Focus groups using semi-structured interviews were conducted with volunteers and nurses at the end of the pilot study. Results LOS was reduced by 6.36 days (U=34, P=0.072) for infants with NAS in the volunteer cuddling program. Focus groups with both bedside nurses and program volunteers described a positive impact of cuddling programs on infants, families, staff, and volunteers alike. Conclusions The study results suggest that the volunteer cuddling program may reduce LOS in infants with NAS and have potential economic savings on hospital resources. However, larger prospective cohort studies are needed to confirm these results.

scholarly journals Transcriptome Ortholog Alignment Sequence Tools (TOAST) for Phylogenomic Dataset Assembly

2020 ◽  
Author(s):  
Dustin J. Wcisel ◽  
J. Thomas Howard ◽  
Jeffrey A. Yoder ◽  
Alex Dornburg
Keyword(s):  
Missing Data ◽  
Open Source ◽  
Research Question ◽  
Single Copy ◽  
Sequence Alignments ◽  
Multiple Sequence ◽  
Multiple Sequence Alignments ◽  
Sequencing Technologies ◽  
Phylogenomic Analyses ◽  
The Impact

Abstract Background Advances in next-generation sequencing technologies have reduced the cost of whole transcriptome analyses, allowing characterization of non-model species at unprecedented levels. The rapid pace of transcriptomic sequencing has driven the public accumulation of a wealth of data for phylogenomic analyses, however lack of tools aimed towards phylogeneticists to efficiently identify orthologous sequences currently hinders effective harnessing of this resource. Results We introduce TOAST, an open source R software package that can utilize the ortholog searches based on the software Benchmarking Universal Single-Copy Orthologs (BUSCO) to assemble multiple sequence alignments of orthologous loci from transcriptomes for any group of organisms. By streamlining search, query, and alignment, TOAST automates the generation of locus and concatenated alignments, and also presents a series of outputs from which users can not only explore missing data patterns across their alignments, but also reassemble alignments based on user-defined acceptable missing data levels for a given research question. Conclusions TOAST provides a comprehensive set of tools for assembly of sequence alignments of orthologs for comparative transcriptomic and phylogenomic studies. This software empowers easy assembly of public and novel sequences for any target database of candidate orthologs, and fills a critically needed niche for tools that enable quantification and testing of the impact of missing data. As open-source software, TOAST is fully customizable for integration into existing or novel custom informatic pipelines for phylogenomic inference.

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