A/B Contracts

This paper aims to improve the practical applicability of the classic theory of incentive contracts under moral hazard. We establish conditions under which the information provided by an A/B test of incentive contracts is sufficient for answering the question of how best to improve a status quo incentive contract, given a priori knowledge of the agent’s monetary preferences. We assess the empirical relevance of this result using data from DellaVigna and Pope’s (2018) study of a variety of incentive contracts. Finally, we discuss how our framework can be extended to incorporate additional considerations beyond those in the classic theory. (JEL D82, D86, D91)

False Discovery in A/B Testing

We investigate what fraction of all significant results in website A/B testing is actually null effects (i.e., the false discovery rate (FDR)). Our data consist of 4,964 effects from 2,766 experiments conducted on a commercial A/B testing platform. Using three different methods, we find that the FDR ranges between 28% and 37% for tests conducted at 10% significance and between 18% and 25% for tests at 5% significance (two sided). These high FDRs stem mostly from the high fraction of true null effects, about 70%, rather than from low power. Using our estimates, we also assess the potential of various A/B test designs to reduce the FDR. The two main implications are that decision makers should expect one in five interventions achieving significance at 5% confidence to be ineffective when deployed in the field and that analysts should consider using two-stage designs with multiple variations rather than basic A/B tests. This paper was accepted by Eric Anderson, marketing.

Hubungan Faktor Risiko Dental Ergonomi dengan Keluhan Subjektif Musculoskeletal Disorders (MSDs) pada Dental Assistant

One of the hazards in dentistry is dental ergonomic. A working problem that can be caused by ergonomic hazards is Musculoskeletal Disorders (MSDs). The dental assistant is one of the jobs that have a risk for the occurrence of abnormalities in the musculoskeletal system. Based on the preliminary study on dental assistants that work in Pontianak City showed that 85% of people had musculoskeletal complaints on the legs, 71,4% had complaints on the calf, and 57,1% had complaints on the shoulder and upper back. The aim of this research is to find out the correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs) on dental assistants. The type of this research was a quantitative study with an analytical observational approach using a cross-sectional design. The research was conducted in Pontianak City in August 2021. The population of this research is 48 respondents and the samples were chosen using the total sampling technique. The instrument that used in this research were collected from the risk factors of dental ergonomics and Nordic Body Map (NMB) questionnaires which were later analyzed using Kendall's tau-b test. The result of this research is risk factors of dental ergonomics in the low category is 54,20%. The subjective complaints of Musculoskeletal Disorders (MSDs) in the low category is 68,80%. Based on Kendall's tau-b test showed that P. Value is 0,601 > 0,05 it means that there is no correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs). The conclusion of this research is there is no correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs) on dental assistants. For further research is expected to examine other risk factors that can cause subjective complaints of Musculoskeletal Disorders (MSDs). Salah satu unsur bahaya dalam dunia kedokteran gigi adalah dental ergonomi. Masalah kerja yang dapat ditimbulkan akibat bahaya ergonomi adalah Musculoskeletal Disorders (MSDs). Pekerjaan dental assistant merupakan salah satu pekerjaan yang memiliki risiko untuk terjadinya keluhan pada sistem musculoskeletal. Hasil studi pendahuluan pada dental assistant yang bekerja di wilayah Kota Pontianak menunjukkan bahwa 85% responden mengalami keluhan musculoskeletal pada bagian kaki, 71,4% pada bagian betis, dan 57,1% pada bagian bahu dan punggung atas. Tujuan penelitian ini adalah untuk mengetahui hubungan antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs) pada dental assistant. Jenis penelitian ini adalah penelitian kuantitatif dengan pendekatan observasional analitik menggunakan rancangan cross-sectional. Penelitian ini dilakukan di Kota Pontianak pada bulan Agustus 2021. Populasi dalam penelitian ini adalah 48 responden dan pengambilan sampel menggunakan teknik total sampling. Instrumen dalam penelitian ini menggunakan kuesioner faktor risiko dental ergonomi dan kuesioner Nordic Body Map (NBM). Analisis data menggunakan uji Kendall’s Tau-B. Hasil dari penelitian ini adalah faktor risiko dental ergonomi berada pada kategori rendah (54,20%). Keluhan subjektif Musculoskeletal Disorders (MSDs) berada pada kategori rendah (68,80%). Hasil analisis data menunjukkan nilai P. Value sebesar 0,601 > 0,05 sehingga tidak terdapat hubungan antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs). Kesimpulan dari penelitian ini adalah tidak terdapat hubungan yang bermakna antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs) pada dental assistant. Penelitian selanjutnya diharapkan dapat mengkaji faktor-faktor risiko lain yang dapat menyebabkan keluhan subjektif Musculoskeletal Disorders (MSDs).

Hubungan Faktor Risiko Dental Ergonomi dengan Keluhan Subjektif Musculoskeletal Disorders (MSDs) pada Dental Assistant

One of the hazards in dentistry is dental ergonomic. A working problem that can be caused by ergonomic hazards is Musculoskeletal Disorders (MSDs). The dental assistant is one of the jobs that have a risk for the occurrence of abnormalities in the musculoskeletal system. Based on the preliminary study on dental assistants that work in Pontianak City showed that 85% of people had musculoskeletal complaints on the legs, 71,4% had complaints on the calf, and 57,1% had complaints on the shoulder and upper back. The aim of this research is to find out the correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs) on dental assistants. The type of this research was a quantitative study with an analytical observational approach using a cross-sectional design. The research was conducted in Pontianak City in August 2021. The population of this research is 48 respondents and the samples were chosen using the total sampling technique. The instrument that used in this research were collected from the risk factors of dental ergonomics and Nordic Body Map (NMB) questionnaires which were later analyzed using Kendall's tau-b test. The result of this research is risk factors of dental ergonomics in the low category is 54,20%. The subjective complaints of Musculoskeletal Disorders (MSDs) in the low category is 68,80%. Based on Kendall's tau-b test showed that P. Value is 0,601 > 0,05 it means that there is no correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs). The conclusion of this research is there is no correlation between risk factors of dental ergonomics and subjective complaints of Musculoskeletal Disorders (MSDs) on dental assistants. For further research is expected to examine other risk factors that can cause subjective complaints of Musculoskeletal Disorders (MSDs). Salah satu unsur bahaya dalam dunia kedokteran gigi adalah dental ergonomi. Masalah kerja yang dapat ditimbulkan akibat bahaya ergonomi adalah Musculoskeletal Disorders (MSDs). Pekerjaan dental assistant merupakan salah satu pekerjaan yang memiliki risiko untuk terjadinya keluhan pada sistem musculoskeletal. Hasil studi pendahuluan pada dental assistant yang bekerja di wilayah Kota Pontianak menunjukkan bahwa 85% responden mengalami keluhan musculoskeletal pada bagian kaki, 71,4% pada bagian betis, dan 57,1% pada bagian bahu dan punggung atas. Tujuan penelitian ini adalah untuk mengetahui hubungan antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs) pada dental assistant. Jenis penelitian ini adalah penelitian kuantitatif dengan pendekatan observasional analitik menggunakan rancangan cross-sectional. Penelitian ini dilakukan di Kota Pontianak pada bulan Agustus 2021. Populasi dalam penelitian ini adalah 48 responden dan pengambilan sampel menggunakan teknik total sampling. Instrumen dalam penelitian ini menggunakan kuesioner faktor risiko dental ergonomi dan kuesioner Nordic Body Map (NBM). Analisis data menggunakan uji Kendall’s Tau-B. Hasil dari penelitian ini adalah faktor risiko dental ergonomi berada pada kategori rendah (54,20%). Keluhan subjektif Musculoskeletal Disorders (MSDs) berada pada kategori rendah (68,80%). Hasil analisis data menunjukkan nilai P. Value sebesar 0,601 > 0,05 sehingga tidak terdapat hubungan antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs). Kesimpulan dari penelitian ini adalah tidak terdapat hubungan yang bermakna antara faktor risiko dental ergonomi dengan keluhan subjektif Musculoskeletal Disorders (MSDs) pada dental assistant. Penelitian selanjutnya diharapkan dapat mengkaji faktor-faktor risiko lain yang dapat menyebabkan keluhan subjektif Musculoskeletal Disorders (MSDs).

Trent Brick Panel: innovative envelope system designed according latest UK national fire and energy performance regulations

In November 2018, following the Grenfell Tower tragedy in London, the Ministry of Housing, Communities & Local Government (MHCLG) introduced an amendment to the Building Regulations 2010, which outlined stricter rules banning the use of combustible materials defined by the new Building Regulation 7(2). This change had a significant impact since early 2019, on the materials and systems that can be used in the construction sector. In 2020, the global pandemic caused by the diffusion of the COVID-19 virus represented a new challenge for the industry, with implications on programme certainty, material procurement, workforce management, moving towards offsite manufacture. The development of the Trent Brick Panel is set against this historical and social context. The envelope prototype is the opportunity for innovation that follows the turn of events. The offsite manufacturing of glass-reinforced concrete panel, mimicking several finishes, is the result of a design investigation carried out with the market-leading actors: developers, main contractors, subcontractors, engineering consultancies, architects, local authorities and warranty providers. The research aims to give an overview of the design principles, sequence and buildability study, assessed weathering performance according to CWCT Sequence B test and fire performance.

Развитие мотивации обучающихся на примере творческой деятельности Димаша Кудайбергена

Проблемой в вузах искусства является развитие профессионально-ориентированной мотивации при подготовке обучающихся. Целью исследования является модернизация парадигм образования в вузах искусства: научно-педагогическое обоснование мотивации обучающихся на примере творческой деятельности популярного певца Динмухамеда Кудайбергена, известного под сценическим псевдонимом Димаш Кудайберген / Dimash Kudaibergen, выступающего под брендом DQ, магистра искусств Казахстана. Влияние внешних факторов современного медиапространства стимулирует внутренние ресурсы студентов к развитию мотивации в их творческой деятельности. Развитие мотивации является актуальной проблемой для студентов бакалавриата и магистратуры, обучающихся по образовательным программам «Искусство». Новизна исследования – рассмотрение мотивации на примере творческой деятельности популярного певца Димаша Кудайбергена, казахстанского магистранта. В статье рассмотрены педагогические аспекты, определяющие мотивацию; содержание профессиональной компетентности в творческой деятельности; подходы, критерии; методы теоретического анализа концепций формирования профессиональной компетентности студентов и корреляционного анализа по критерию Kendall Tau b test. По результатам исследования разработан мотивационный критерий с показателями и дескрипторами для уровней профессиональной компетентности, сформулированы выводы и рекомендации по развитию мотивации бакалавров и магистрантов, обучающихся по направлению «Искусство» в Казахстане.

Antibiotic-associated diarrhea in hospital: frequency and prophylaxis

The aim. To analyze the prevalence of antibiotic-associated diarrhea (AAD) caused by Clostridium difficile in a hospital setting.Materials and methods. 93 patients with 3 or more episodes of unformed stool (diarrhea) for two consecutive days or more, developed after the use of antibiotics, were monitored. All patients underwent rapid stool analysis for the presence of Clostridium difficile A and B toxins using the X/pert C. diff toxin A/B test.Results. Toxins A and/or B of Clostridium difficile were detected in 32 patients (34.4 %). The remaining patients (n = 61; 65.6 %) had idiopathic AAD. The most of the patients who were found to have Clostridium difficile toxins in the feces were in the infarction department, cardiology intensive care and trauma departments, i. e. they had severe diseases associated with reduced immunity and inactivity.Conclusions. The prevalence of AAD caused by Clostridium difficile in hospital settings is high. It is recommended to prescribe drugs for the correction of disorders of the gastrointestinal microflora from the first day of antibiotic therapy, since this will significantly reduce the prevalence of clinical manifestation of diarrhea associated with Clostridium difficile.

The Upworthy Research Archive, a time series of 32,487 experiments in U.S. media

The pursuit of audience attention online has led organizations to conduct thousands of behavioral experiments each year in media, politics, activism, and digital technology. One pioneer of A/B tests was Upworthy.com, a U.S. media publisher that conducted a randomized trial for every article they published. Each experiment tested variations in a headline and image “package,” recording how many randomly-assigned viewers selected each variation. While none of these tests were designed to answer scientific questions, scientists can advance knowledge by meta-analyzing and data-mining the tens of thousands of experiments Upworthy conducted. This archive records the stimuli and outcome for every A/B test fielded by Upworthy between January 24, 2013 and April 30, 2015. In total, the archive includes 32,487 experiments, 150,817 experiment arms, and 538,272,878 participant assignments. The open access dataset is organized to support exploratory and confirmatory research, as well as meta-scientific research on ways that scientists make use of the archive.

Leading students towards a new soft-skills perspective: development for employment

Aim. Based on similar studies, this research work aims to investigate the perception of students and Higher Education Institutions (HEIs) of learning about the importance of soft skills for their education and employment since these skills are increasingly sought-after by potential employers. Methods. The Kendall Tau b test and Mann Whitney U test have been applied to show the relationship between soft skills and job preparedness for students. This study investigates a selection of 100 students from a private HEI (UBT College) and 100 students from a public HEI (University “Haxhi Zeka”), both in Kosovo. A total of 200 valid responses were collected from July to September 2020. Goldsmith inventory for 15 soft skills has been distributed as a questionnaire has been distributed to the students of these universities. Results and conclusion. The research results indicate that in soft skills development of the UBT College students is significantly higher than the soft skills developed of the University “Haxhi Zeka” students. The findings also show that most of the students believe that their actual soft skills were at a less than the desired level. Practical application. This research implicates the Higher Education Institutions to consider the soft skills as an important tool for enhancing graduates’ employability. The results indicate the need to reconsider the curriculum by embedding soft skills on it. The students’ perception on soft skills is a contribution not only for the universities considered in this research but also for all graduates in HEIs in Kosovo, since the curriculum does not change much among universities. According to Eurostat the unemployment youth rate in Kosovo is about 55.4% and for this reason the results will help the HEIs to rethink about their students’ future employment opportunities. Originality. This is the only study done in Kosovo about graduates’ soft skills and employment and it provides information about a concerning problem in the country. This paper suggests initiatives to upgrade students’ soft skills and to improve their perspective on their future employment.

Bayesian Inference for the A/B Test: Example Applications with R and JASP

Popular in business, psychology, and the analysis of clinical trial data, the A/B test refers to a comparison between two proportions. Here we discuss two Bayesian A/B tests that allow users to monitor the uncertainty about a difference in two proportions as data accumulate over time. We emphasize the advantage of assigning a dependent prior distribution to the proportions (i.e., assigning a prior to the log odds ratio). This dependent-prior approach has been implemented in the open-source statistical software programs R and JASP. Several examples demonstrate how JASP can be used to apply this Bayesian test and interpret the results.