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The two aims of this study were to: 1) identify the 100 most impactful contributors to English-language gerontological journals, and 2) map their respective disciplinary affiliations to help illuminate the perspectives shaping gerontological discourse. Toward that end, we conducted a secondary data analysis of a publicly available database of the world's leading scientists. After extracting all scientists in the gerontological category, we rank ordered them according to a composite measure of scholarly impact that controls for self-citations and author order while also calculating other bibliometric statistics. Disciplinary affiliations were assigned based upon the Classification of Instructional Programs codes developed by the National Center for Education Statistics at the United States Department of Education. The results reveal the mean contributor to the gerontological literature published 241.15 (SD = 203.95) papers and – after correcting for self-citations – had an h-index of 50.05 (SD = 25.00), and an hm-index 23.67 (SD = 7.50). A diverse array of professional affiliations characterized the contributors with a plurality being located in the health professions category, followed by the biological and biomedical science, and social sciences categories. The results reveal that gerontology is home to some of the world's leading scientists. Leveraging their expertise can help advance the field's collective knowledge development. [ABSTRACT FROM AUTHOR]

The University of Alabama at Birmingham Heersink School of Medicine established the Pittman Scholars Program in 2015 to elevate scientific impact and to support the recruitment and retention of highly competitive junior faculty. The authors examined the impact of this program on research productivity and on faculty retention. The authors evaluated publications and extramural grant awards and available demographic data for the Pittman Scholars compared to all junior faculty in the Heersink School of Medicine. From 2015 to 2021, the program awarded a diverse group of 41 junior faculty members across the institution. For this cohort, ninety-four new extramural grants were awarded and 146 grant applications were submitted since the inception of the scholar award. Pittman Scholars published a total of 411 papers during the term of the award. The faculty retention rate of the scholars was 95%, comparable to that of all Heersink junior faculty, with 2 recipients being recruited to other institutions. The implementation of the Pittman Scholars Program has been an effective strategy to celebrate scientific impact and acknowledge junior faculty members as outstanding scientists at our institution. The Pittman Scholars award allows junior faculty to use funds for their research program, publications, collaborations, and career advancement. The Pittman Scholars are recognized at local, regional, and national levels for the work they are contributing to academic medicine. The program has served as an important pipeline faculty development program and an avenue for individual recognition for research-intensive faculty. [ABSTRACT FROM AUTHOR]

This study identified the 100 most impactful global contributors to religion journals and mapped their respective disciplinary affiliations. To conduct this investigation, we performed a secondary data analysis of a Scopus-derived database featuring the world's leading scientists. The mean contributor published 51.93 papers, had an h-index of 13.57, and an hm-index 11.50. Most contributors were located in the USA with the most common disciplinary affiliations being religion, non-specialized (n = 22), sociology, non-specialized (n = 21), sociology of religion (n = 20), and theology (n = 11). The results reveal that religion discourse is populated by some of the leading scholars in the world. Leveraging their expertise can help advance the field's knowledge development. [ABSTRACT FROM AUTHOR]

This paper seeks to understand the relationship, in historic preservation, between equity/social justice and the field's intra-disciplinary scholarship by using a critical heritage studies lens. Intra-disciplinary scholarship is defined as the scholarly literature produced by the 58 tenured and tenure-track faculty associated with historic preservation degree programmes in the United States through the end of 2018. A content analysis of this literature shows a general lack of engagement by authors on issues related to the public's needs, including topics related to justice, equity, diversity, and inclusion. A citation analysis of this literature reveals meagre faculty productivity and low impact for intra-disciplinary preservation scholarship. In order for the field to sustain itself, it needs to reconsider its anti-intellectual tendencies, increase its socially relevant scholarly publications, and embrace more critical, people-centred approaches. [ABSTRACT FROM AUTHOR]

Purpose: This study identified the top 100 most impactful global contributors to social work journal scholarship. Methods: To conduct this descriptive study, we used a publicly available database of the world's leading scientists. After extracting all scholars in the social work category, we rank ordered them according to a composite measure of scholarly impact that controls for self-citations and author order. Results: All identified contributors to the profession's journals ranked highly relative to the larger global population of published scientists. Furthermore, 23 individuals were in the top 100,000 scientists globally. Scholars were based in seven different nations and most had solid social work credentials according to three measures: current affiliation in a social work program and Master of Social Work/doctoral degree status. Conclusions: The results reveal that social work is home to some of the world's leading scientists. Leveraging their skills and knowledge can help advance the profession's collective knowledge development and dissemination. [ABSTRACT FROM AUTHOR]

Much work by criminology and criminal justice scholars assesses and ranks doctoral programs and faculty based on productivity measured as number of articles, journal prestige, and grantspersonship. These state-of-the-field publications provide important information about the subset of Ph.D. programs and their faculty. Less attention is paid in these discussions to productivity among faculty at master's degree granting programs; omitting a considerable bulk of scholars. Using self-report survey data from 34 residential criminal justice master's degree granting programs, the present research explores productivity of faculty by examining a variety of publication outlets and grantspersonship to assess contributions to the field over a five-year period, 2014–2018. This study is a first step in understanding the strengths of master's level program faculty and their representation in the discipline. The paper concludes by outlining future considerations for research to extend the discussion on faculty productivity to scholars from a wider-range of programs. [ABSTRACT FROM AUTHOR]

Midcareer faculty are the "keystone" of academia. Faculty in midcareer experience an increase or change in responsibilities and expectations as well as reduced support and mentorship usually extended to junior faculty. Nonetheless, midcareer can be an ideal time for re-evaluating and defining one's career path and taking advantage of leadership and service opportunities. Successful navigation of midcareer is essential to ensure nursing faculty remain in the academic setting, contribute to nursing science, and have a satisfying career. In this paper, we present strategies midcareer nurse faculty can consider to maintain balance and advance their careers even during challenging times. These strategies include appraising career goals, maintaining and expanding mentoring relationships, seeking and utilizing opportunities for leadership development, selecting service strategically to advance career goals, preparing for the unexpected, maintaining/expanding scholarly productivity, learning when to say yes or no, embracing lifelong learning, and improving visibility of one's work. • Midcareer is an ideal time to appraise career goals and expand mentoring. • Midcareer is an opportunity for leadership development and significant service. • Time management and selective collaborations improve productivity in midcareer. • Improved communication and visibility during midcareer may extend influence. • Embracing lifelong learning and expecting the unexpected help maintain productivity. [ABSTRACT FROM AUTHOR]

Objective/Hypothesis: The h- index is an objective and easily calculable measure that can be used to evaluate both the relevance and amount of scientific contributions of an individual author. Our objective was to examine how the h- index of academic otolaryngologists relates with academic rank. Study Design: A descriptive and correlational design was used for analysis of academic otolaryngologists' h- indices using the Scopus database. Methods: H- indices of faculty members from 50 otolaryngology residency programs were calculated using the Scopus database, and data was organized by academic rank. Additionally, an analysis of the h- indices of departmental chairpersons among different specialties was performed. Results: H- index values of academic otolaryngologists were higher with increased academic rank among the levels of assistant professor, associate professor, and professor. There was no significant difference between the h- indices of professors and department chairpersons within otolaryngology. H- indices of chairpersons in different academic specialties were compared and were significantly different, suggesting that the use of this metric may not be appropriate for comparing different fields. Conclusions: The h- index is a reliable tool for quantifying academic productivity within otolaryngology. This measure is easily calculable and may be useful when evaluating decisions regarding advancement within academic otolaryngology departments. Comparison of this metric among faculty members from different fields, however, may not be reliable. Laryngoscope, 2013 [ABSTRACT FROM AUTHOR]

In this paper I introduce the theory of gift giving as a possible means to reconcile the contradictions inherent in accountability measures of ‘faculty productivity’ in the American university. In this paper I sketch the theory of gift economies to show how, given the historical ideals that characterize the faculty-student relationship, a theory of gift giving could help us better judge the labor of the faculty. I suggest that it is the relational character of teaching that frustrates accountability measures and that perhaps if viewed as a gift economy—and in particular an economy with ‘reproductive’ ends—we could better grasp the effectiveness of these relationships. [ABSTRACT FROM AUTHOR]

Background: Faculty productivity is essential for academic medical centers striving to achieve excellence and national recognition. The objective of this study was to evaluate whether and how academic Departments of Medicine in the United States measure faculty productivity for the purpose of salary compensation. Methods: We surveyed the Chairs of academic Departments of Medicine in the United States in 2012. We sent a paper-based questionnaire along with a personalized invitation letter by postal mail. For non-responders, we sent reminder letters, then called them and faxed them the questionnaire. The questionnaire included 8 questions with 23 tabulated close-ended items about the types of productivity measured (clinical, research, teaching, administrative) and the measurement strategies used. We conducted descriptive analyses. Results: Chairs of 78 of 152 eligible departments responded to the survey (51% response rate). Overall, 82% of respondents reported measuring at least one type of faculty productivity for the purpose of salary compensation. Amongst those measuring faculty productivity, types measured were: clinical (98%), research (61%), teaching (62%), and administrative (64%). Percentages of respondents who reported the use of standardized measurements units (e.g., Relative Value Units (RVUs)) varied from 17% for administrative productivity to 95% for research productivity. Departments reported a wide variation of what exact activities are measured and how they are monetarily compensated. Most compensation plans take into account academic rank (77%). The majority of compensation plans are in the form of a bonus on top of a fixed salary (66%) and/or an adjustment of salary based on previous period productivity (55%). Conclusion: Our survey suggests that most academic Departments of Medicine in the United States measure faculty productivity and convert it into standardized units for the purpose of salary compensation. The exact activities that are measured and how they are monetarily compensated varied substantially across departments. [ABSTRACT FROM AUTHOR]

This manuscript documents the research productivity over a 10-year period (2007–2016) of marketing faculty at 30 leading marketing departments. We find that median productivity in the top four marketing journals was 0.40 publications per year. We find no meaningful difference in productivity between "quant" and "behavioral" faculty. Furthermore, we find a slow decrease in productivity as faculty's "academic age" increases, but we also find that the most productive members of our community are among the colleagues who received their PhDs 20 to 30 years ago and that academic age is not a good predictor when recent productivity is taken into account. In addition, we find that the departments differ strongly in terms of the concentration of publications among faculty, as measured by the Gini coefficient. Finally, and to our surprise, we find that the number of publications in top journals by the faculty at these 30 schools dropped quite precipitously from the 2007–2011 to the 2012–2016 period. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study that counted articles and the number of pages written on business ethics and published during the five-year period 1995-1999. Individual scholars were ranked on the basis of total articles and total pages published. Institutions were also ranked based on the number of pages and articles their scholars published in selected business ethics journals. This article is the first one to rank schools and individual scholars on the basis of research productivity in business ethics. [ABSTRACT FROM AUTHOR]

ABSTRACTThe University of Alabama at Birmingham Heersink School of Medicine established the Pittman Scholars Program in 2015 to elevate scientific impact and to support the recruitment and retention of highly competitive junior faculty. The authors examined the impact of this program on research productivity and on faculty retention. The authors evaluated publications and extramural grant awards and available demographic data for the Pittman Scholars compared to all junior faculty in the Heersink School of Medicine. From 2015 to 2021, the program awarded a diverse group of 41 junior faculty members across the institution. For this cohort, ninety-four new extramural grants were awarded and 146 grant applications were submitted since the inception of the scholar award. Pittman Scholars published a total of 411 papers during the term of the award. The faculty retention rate of the scholars was 95%, comparable to that of all Heersink junior faculty, with 2 recipients being recruited to other institutions. The implementation of the Pittman Scholars Program has been an effective strategy to celebrate scientific impact and acknowledge junior faculty members as outstanding scientists at our institution. The Pittman Scholars award allows junior faculty to use funds for their research program, publications, collaborations, and career advancement. The Pittman Scholars are recognized at local, regional, and national levels for the work they are contributing to academic medicine. The program has served as an important pipeline faculty development program and an avenue for individual recognition for research-intensive faculty.

Using an exhaustive database on academic publications in mathematics all over the world, we study the patterns of productivity by mathematicians over the period 1984-2006. We uncover some surprising facts, such as the weakness of age related decline in productivity and the relative symmetry of international movements, rejecting the presumption of a massive 'brain drain' towards the US. We also analyze the determinants of success by top US departments. In conformity with recent studies in other fields, we find that selection effects are much stronger than local interaction effects: the best departments are most successful in hiring the most promising mathematicians, but not necessarily at stimulating positive externalities among them. Finally we analyze the impact of career choices by mathematicians: mobility almost always pays, but early specialization does not. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis The h-index, a bibliometric indicator that objectively characterizes the impact of an author's scholarship, is an effective tool that may be considered by academic departments for decisions related to hiring and faculty advancement. Our objective was to characterize the scholarly productivity of academic surgeons from different specialties relative to otolaryngologists. Study Design Analysis of a bibliometric database. Methods The h-indices of 2,429 faculty members within surgical specialties at 20 randomly selected academic institutions were calculated using the Scopus database and were examined to determine relationship with academic rank and comparison among surgical subspecialties. Results The h-index statistically increased with academic rank. Mean h-indices were as follows: assistant professor, 4.37 (range, 2.73-6.69); associate professor, 8.70 (6.53-11.02); professor, 16.44 (13.39-20.45); and chairperson, 20.79 (14.81-27.89). Mean increase between academic rank was 5.47, with the largest increase between the levels of associate professor and professor. Further examination demonstrated statistically significant increases through all academic ranks for most, but not all, individual specialties. Urologists, general surgeons, and neurosurgeons had the highest mean h-indices. Conclusions h-indices among the different surgical specialties vary and are potentially impacted by the number of practitioners as well as research emphasis within a field. The mean h-index of academic otolaryngologists falls in the lower values for academic surgeons. Because this metric varies among different fields, it is most relevant for comparison when examining values within a field. H-indices reliably increase with increasing academic rank through professor and offer a quantifiable and objective alternative to other metrics when evaluating faculty members for academic advancement. [ABSTRACT FROM AUTHOR]

A partial answer is provided to the question "what are the most research productive business school Operations Management departments?" Among the many research rankings published, this research question appears to be unique. Other efforts in Operations Management rank either business schools or entire universities. Our criterion for ordering departments is also unique: publications only by faculty currently employed by the department. Other rankings do not consider the number or title of faculty, thereby providing an advantage to larger and more experienced faculty. This ranking is adjusted for both number of faculty and years of experience. [ABSTRACT FROM AUTHOR]

This essay provides descriptive evidence on the state of under-represented minority (URM) Ph.D. faculty in the accounting academy. Despite the significant growth in URM faculty in the last 26 years, the proportion of URM faculty remains extremely low (below 5 percent). Over 60 percent of URM accounting faculty earn their Ph.D.s at research-intensive institutions, but their employment rate at these institutions, and top-ranked universities, and M.B.A. programs remains low. Although URM faculty are largely excluded from leadership roles in accounting journals, their contributions to research are on par with productivity metrics for all accounting faculty. This essay, the first report of its kind on the state of race in the academy, briefly reviews the relevant existing literature and offers suggestions for future research. This essay also includes recommendations for improving the recruiting and retention of URM faculty and transparency in the publication process aimed at achieving greater inclusiveness in the academy. [ABSTRACT FROM AUTHOR]

Research self-efficacy is important to measure among faculty, given its relationship with scholarly productivity. However, very few measures exist to assess research self-efficacy among faculty, and few of those have evidence of validity. Thus, the Faculty Research Self-Efficacy Scale (FaRSES) was developed, with initial validation occurring among a nationwide sample of social and behavioral science faculty. A second order factor model emerged, where dimensions on the first factor included both (a) General Research Process and Quantitative Research and (b) Qualitative Research. Both first order factors loaded on one general second order factor. Scores on the first and second order FaRSES had strong evidence of reliability and validity. Suggestions for future research are provided. [ABSTRACT FROM AUTHOR]

Quantifying faculty productivity has been of interest since the creation of the Journal Impact Factor. With the electronic age, copious documents can be analyzed to calculate the h-index, which assesses the productivity and impact of the citation. Changing generational characteristics have increased the use of third-party websites and their emerging role in disseminating research justify this pilot study examining the application of altmetrics along with h-index scores to assess Hospitality Management faculty productivity. Findings corroborated the positive correlation between h-index and program recognition and altmetric score. A range of penetration rates regarding altmetric events among hospitality management faculty was found. [ABSTRACT FROM AUTHOR]

This article considers how graduate educators can best prepare their students for writing and publishing academic scholarship, drawing on interviews performed by the coauthors with twenty published scholars from rhetoric and composition. The article also includes specific, practical strategies for academic publishing drawn from the interviews. [ABSTRACT FROM AUTHOR]

Universities are under pressure to increase external research funding, and some federal agencies offer programs to expand research capacity in certain kinds of institutions. However, conflicts within faculty roles and other aspects of university operations influence the effectiveness of particular strategies for increasing research activity. We review conventional approaches to increasing research, focusing on outcomes for individual faculty members and use one federally-funded effort to build cancer-related research capacity at a public university as an example to explore the impact of various strategies on research outcomes. We close with hypotheses that should be tested in future formal studies. [ABSTRACT FROM AUTHOR]

Academic careers and institutional reputations are closely linked with the ability to secure funding and publish work. In today's competitive environment, it is essential for research to be clearly communicated. In our experience, many researchers need assistance with communication skills, and institutions that offer professional services in grant, manuscript and project management have an advantage in the development of their faculty and trainees. A review of the literature shows that some institutions offer centralized proposal development resources and personnel to assist with grant writing, some institutions offer workshops and lectures designed to improve researchers' writing skills for grants and/or manuscripts, and fewer institutions offer departments focused specifically on editing manuscripts. In the fall of 2009, the University of Kentucky's (UK) Markey Cancer Center (MCC) developed an infrastructure, the Research Communications Office (RCO), to enhance faculty productivity. The RCO exists to provide: expertise in scientific editing of manuscripts for academic publishing; editing and management of research, training, and career development grants; project management for multi-component and institutionally complex grants; facilitation and tracking of all MCC pilot funding mechanisms; tracking all research outcomes; preparation of graphics for presentations, posters, publications and grants; marketing and design expertise for outreach endeavors; the planning and execution of internal and external communications; and MCC web content creation and maintenance. A successful and valued service for MCC, the RCO has totaled more than 1,400 projects over six years, growing from 189 projects when tracking began in 2010 to 294 in 2015. This article will discuss why and how the RCO was created at the MCC, and in doing so, provide a framework for how the RCO model can be successfully implemented at other institutions interested in offering professional editing and management of grants and manuscripts. [ABSTRACT FROM AUTHOR]

The article focuses on gender disparities in scholarly productivity within academic otolaryngology departments. The article reports that disparities in women participation in surgical specialties is due to lack of mentoring and concerns about work-life balance. It concludes that men had higher h-index (Hirsch index) that measures the research contributions made and had higher research productivity rates and academic ranks than women in academic otolaryngology.

Objectives/Hypothesis: Assessment of scholarly productivity as measured by research output is a key component of decisions regarding appointment and advancement in academic otolaryngology. An increasing number of graduating residents are pursuing postresidency fellowships, and evaluation of research productivity among these subspecialists is important in determining their role in academic otolaryngology departments. The h-index is a reliable indicator of research productivity, as it takes into account both quantity and relevance of research contributions. Our objective was to evaluate and compare trends in research productivity among the various otolaryngology subspecialties. Study Design: Analysis of research productivity trends among otolaryngology subspecialties using the h-index. Methods: Faculty members from 92 academic otolaryngology departments were organized by subspecialty and academic rank, and their research productivity, as measured by the h-index, was calculated using the Scopus database. Results: Fellowship-trained otolaryngologists in academic programs had higher h-indices than non-fellowship-trained otolaryngologists. Head and neck surgeons and otologists had significantly higher research productivity than their peers in other otolaryngology subspecialties. Analysis of the subspecialties of chairpersons indicated that 62% were either head and neck surgeons or otologists. Conclusions: Fellowship-trained otolaryngologists had higher h-indices, and faculty members trained in the subspecialties with the highest research productivity were disproportionately represented in positions of leadership within academic otolaryngology, probably reflecting the importance of research contributions in the academic advancement process, although other factors, such as educational contributions and clinical performance, may also be important factors. Laryngoscope, 2012 [ABSTRACT FROM AUTHOR]

Similar to trends in postsecondary education across the world, today's US universities are an increasing mix of native and foreign-born scholars. US institutions are experiencing a growing number of international faculty members, but there is limited literature examining foreign-born faculty who work in US institutions and how outputs from foreign-born faculty compare to US-born natives. Using data from the 2004 National Survey of Postsecondary Faculty (NSOPF:04), this study examines difference in faculty members' research productivity at doctoral-granting institutions by foreign/US-born status controlling for select individual and institutional characteristics. Findings show that foreign-born faculty members spend more time on research and less time on undergraduate instruction than US-born peers, and this may contribute to their higher levels of production. Implications are discussed that consider how to ensure diverse faculty communities that lead to strong research and knowledge production. [ABSTRACT FROM AUTHOR]

Recession is currently causing a resurgence of the academic serials crisis. Profit-mongering by commercial publishers is once again denounced as the key driver of the crisis. However, a critical analysis of institutional and bibliometric data does not reveal excessive corporate greed in recent years; instead, it suggests that the present hurdles stem largely from years of inadequate budget allocations to academic libraries and from a publishing frenzy fuelled by simplistic methods of evaluating faculty productivity. To prevent what is likely to be the publishing equivalent of a tsunami in the next few years, universities and research institutions urgently need to re-emphasize quality over quantity in the publishing process, and they must find ways to include peer-reviewing efficiency among their criteria for productivity and impact. Achieving these goals will require concerted efforts by researchers, librarians, and publishers. [ABSTRACT FROM AUTHOR]

In this article, authors report one College of Nursing’s efforts to address the challenges of multiple academic role expectations by establishing faculty interest groups to promote collaborative scholarship. The background of the project is described in terms of past and recent academic, financial, and environmental influences. Collaborative scholarship is defined. Literature related to faculty productivity, variations in collaborative scholarship within and across disciplines, and incentives to motivate and reward faculty productivity are discussed. An evaluation of one faculty interest group’s process is reported. Amey and Brown’s Interdisciplinary Collaboration Model dimensions were used to analyze achievements and challenges. Organizational restructuring and disbandment of these groups provided a second opportunity to reflect on lessons learned. One perspective about the process and educational and professional implications of collaborative scholarship that would be of interest to faculty is provided. Lessons learned may inform other faculty facing the same task. [ABSTRACT FROM AUTHOR]

To grow and prosper in an era when university departments are increasingly assessed comparatively and critically by national systems of accountability and ranking, planning schools need data that reflect the wide range of activities undertaken by planning educators. Recent developments surrounding planning school assessment in U.S. planning schools are considered in light of the history of university unit performance measurement internationally, and suggestions are made for development of a robust system of planning school assessment that includes the breadth of academic planners' work. [ABSTRACT FROM AUTHOR]

As state budget allocations for higher education decrease, "specialty" programs such as gerontology must continually demonstrate their productivity. State and private universities increasingly rely on student credit hours (SCH) or tuition generated, which is making it difficult for many gerontology programs to expand. The School of Aging Studies at the University of South Florida has achieved a 236% increase in annual SCH productivity over the past 5 years by methods including qualifying courses for university liberal arts requirements, and designing and cross-listing interdisciplinary courses. This increased productivity has supported program expansion and led to beneficial outreach to students from diverse majors. doi:10.1300/J021v28n01_03 [ABSTRACT FROM PUBLISHER]

This article describes the establishment in fall 2002 of a School of Education Research Center designed to support faculty in increasing productivity and quality in research. Details are provided about center goals, services, staffing, space, resources, and logistics during the first year of operation. In addition, data are shared about faculty usage of the Center, the level of faculty satisfaction with center services in the first year, and initial increases in faculty productivity. The article concludes with plans for continued data collection to monitor the impact of the Center, a discussion of lessons learned at this point in the Center's development, and possibilities for the evolution of the Center. [ABSTRACT FROM AUTHOR]

Abstract: The average faculty productivity have been described as a rapid rise-short peak-gradual decline pattern. Way et al. (2017) have studied this pattern for faculty careers in Computer Science in North America using a piecewise linear model. In this paper, we use a similar methodology and study trajectories (N = 20655) of the Brazilian Computer Science community. First, we have evaluated how the median publication count of researchers is related to institution prestige and public vs. private administration. Second, we have studied how the annual publication rates have increased and its variation according to prestige ranks of institutions. Third, we have found the average trajectory can indeed be described as the canonical rapid increase and slower decrease in productivity. For individual trajectories of senior researchers we have observed only 4.5% of trajectories are well explained by the conventional narrative of rapid rise and gradual decline model. We also have found polynomial models of degrees 1 to 3 explain almost 63.1% of trajectories. The rest of trajectories are considered unstable and not well explained by neither of approaches.