Mutual Fit Research Articles

Dynamic and static mutual fitting for action recognition

Action recognition is intended to classify a video into a certain category by aggregating and summarizing its temporal and spatial information. Existing methods have achieved remarkable performance on the standard datasets. However, how to accurately recognize the action under occluded scenarios remains the major challenge in practical applications and is barely explored. Although previous augmentation methods have made some efforts by introducing additional modalities to deal with occlusion cases, the continuous occlusion related to temporal in the video is rarely focused. To tackle this issue, this paper takes the sample augmentation and feature representation into consideration. Specifically, we design a Dynamic Temporal-aware Erasing (DTE) augmentation strategy to enrich the occlusion samples. The proposed DTE builds upon an explicit analysis conditioned with temporal dimension along with the actors’ trajectories, which ensures the capability of carrying the temporal relation to an arbitrary spatial augmentation setting. Specifically, DTE makes the added augmentation samples more temporally consistent with obtaining the motion trajectories of the actors, enhancing the robustness against occlusions. Besides, we revisit the necessity of diverse backgrounds and propose Dynamic and Static Mutual Fitting (DSMF) to optimize the action recognition model. DSMF incorporates background auxiliary mutual fitting actors to distinguish features, which learns a smooth representation with the global temporal consistency. Extensive experiments conducted on standard benchmarks have proved that the proposed DSMF achieves competitive performance over powerful competitors.

Building Evaluation Capacity for Integrated Care: Lessons from an Embedded Researcher Program

Introduction: Evaluation has an important role to play in supporting integrated care. By collecting data early and often, care teams can better learn and adapt as new models of care are implemented. While the benefits of evaluation are well known, organizations may lack the capacity to conduct these well. This is particularly true of smaller organizations, where research is often seen as a luxury rather than a ‘must have.’
 This paper presents lessons from the OHT Impact Fellows, a training program that places postdoctoral fellows in healthcare organizations where they support implementation and evaluation of integrated care projects. Since its launch in 2021, the program has placed 22 fellows in health teams across Ontario, Canada. Drawing on the collective experience of these fellows, we offer suggestions on how to build evaluation capacity for integrated care.
 Background: Introduced by the provincial government in 2019, Ontario Health Teams (OHTs) are a new way of organizing care in Ontario. The primary goal of OHTs is to deliver care in a more integrated way, with care providers in different sectors (e.g., hospitals, primary care, home and community care) working as one coordinated team. To support their development, the government has funded several support programs, including the OHT Impact Fellows. Designed with input from researchers, funders (government), and knowledge users (clinicians, health leaders, and patients), this program provides on-the-ground support tailored to the needs of host OHTs. 
 The Program: Each year, OHTs are invited to submit expressions of interest to host a research fellow. Soon afterwards, a call is issued for fellowship applicants. After a rigorous selection process, fellows are matched with a host OHT based on their mutual fit. This process ensures that the skills and interests of fellows match the needs of their host organizations. Fellows then spend one year embedded in an OHT, supporting evaluation within and learning across OHTs. Fellows are matched with a host and academic mentor and supported with ongoing training and professional development opportunities. At the end of their fellowship, participants provide detailed feedback on the program through a survey.
 Results: Based on this survey data, here are some learnings so far:
 
 1. Fellows were seen as highly impactful in supporting local projects and building OHT capacity. They were seen as moderately impactful in supporting learning across OHTs.
 2. Fellows were extremely productive, sharing knowledge through conference presentations (>30), technical reports (>20), and internal briefings (>90) in one year.
 3. Many fellows worked on projects that engaged patients and caregivers, often using a co-design approach. Patient engagement and co-design are among the top topics for which fellows have requested additional training.
 4. Building evaluation capacity is as much about culture as analytical ability. For some organizations, ‘evaluation’ is a scary word that needs to be demystified before it can be embraced.
 Next Steps: We hope to offer a third round of fellowships in 2023.
 Audience: This presentation will be of interest to clinician-scientists, health leaders, researchers, and others interested in evaluation and its use in integrated care settings.

Stronger Together: Cancer Clones Cooperate to Alleviate Growth Barriers in Critical Cancer Progression Transitions.

Hershey and colleagues recently showed how clones in a triple-negative breast cancer cell line cooperate for their mutual fitness benefit. In this system, clones exchange soluble metabolites to increase their in vitro growth rate at low population densities, therefore mitigating the documented growth barrier that reduces individual fitness in small tumor cell populations (Allee effect). Such cooperation could aid important transitions in cancer progression in which cancer cell populations are small, like invasion or metastasis. Using orthotopic transplantation, the authors demonstrate that this cooperation is functional in one such transition in vivo, increasing the metastatic load and number of metastases, which are usually polyclonal. Together, these findings highlight the need to consider ecologic interactions to properly understand tumor growth dynamics, and how they complement the standing evolutionary model of cancer progression in our quest to understand and treat cancer.

CSR employer branding, organisational identification, person–organisation fit and employee retention: a dual mediation model

PurposeCorporate social responsibility (CSR) is gaining recognition and value among researchers, academicians and business professionals. Drawing on theories of social identity and person–organisation fit, the present research propounds a model that investigates the role of CSR branding in influencing employee retention.Design/methodology/approachThe paper is based on primary survey data from 348 employees working in organisations in the Indian industrial hubs. The study uses the regression and PROCESS macro model to analyse relationship among study variables.FindingsThe study indicated how CSR initiatives could help organisations handle the threat of high turnover storm all over the world, thereby retaining the employees with a high set of skills. Moreover, the paper connotes that employee retention is influenced directly by CSR branding as well as indirectly under the presence of organisational identification and person–organisation fit (mediators).Practical implicationsResults suggest the role of a positive identity and a mutual fit as significant predictors of employee retention. The implications for future research on CSR, employees' stay intentions, employees' identification and value congruence are further discussed in light of the findings.Originality/valueThe novelty of this research insists on shedding light on the indirect mechanisms linking CSR to employee retention that has been overlooked so far, particularly in the Indian setting; studies on an integrated model of organisational identification and person–organisation fit are limited.

Networking between helminths, microbes, and mammals

Just as mammals have coevolved with the intestinal bacterial communities that are part of the microbiota, intestinal helminths represent an important selective force on their mammalian host. The complex interaction between helminths, microbes, and their mammalian host is likely an important determinant of mutual fitness. The host immune system in particular is a critical interface with both helminths and the microbiota, and this crosstalk often determines the balance between tolerance and resistance against these widespread parasites. Hence, there are many examples of how both helminths and the microbiota can influence tissue homeostasis and homeostatic immunity. Understanding these processes at a cellular and molecular level is an exciting area of research that we seek to highlight in this review and that will potentially guide future treatment approaches.

How Motivation, Nomophobic Design and Environmental Demands Predict Students’ Media Multitasking when Participating in Online Courses During COVID-19: An Empirical Study with a HCI Time and Temporality Lens

Abstract There is an emerging shift in human–computer interaction (HCI) research from things to events and towards time and temporality as a design material, which is made even more urgent by the unique time of the COVID-19 period. This paper pushes this shift forwards by investigating factors and the way that these shape online media multitasking behaviour over time during COVID-19. We model the factors along the WHAT and HOW dimensions of the HCI-over-Time model (HCIoT) with self-report data from 117 university students and objective behavioural data from 40 university students, who participated in an online course over 2 weeks during COVID-19. The results indicated a pervasiveness of media multitasking behaviour over time in an online course, driven by individual factors and enhanced by their mutual fit. Based on interpretation of our data, we suggest conceptualizing the COVID-19 period as the larger temporal environment in the HCIoT model. The discussion further explains how the broader idea of human–computer-environment fit is significant to understand HCIoT through an interaction lens. We discuss methodological issues related to differentiating between self-report and behavioural measures when applying the HCIoT model. The conclusion supports the feasibility and significance of conceptualizing media multitasking during COVID-19 as temporal HCI and of further developing and operationalizing the HCIoT model by using both behavioural and self-report measures.

Is cesarean section a clinical marker for psychiatric and sleep disorder in young mothers? A cross-sectional study from rural South India.

Gestation and postnatal period are important stages in a woman's life. The type of delivery, vaginal delivery (VD) or cesarean Section (CS), is determined by maternal and fetal factors and their mutual fit. The type of delivery has consequences on the health and well-being of the mother and the newborn. Postpartum psychiatric disorders have been found to be both positively and negatively associated with the mode of delivery and demographic and clinical variables of the postpartum mothers. In view of the foregoing, a comprehensive investigation of the demographic and clinical variables and a range of psychiatric disorders among postpartum women delivered both vaginally and by CS in a rural tertiary care hospital in South India was proposed. All consecutive women delivered vaginally and by CS attending Maternal and Child Clinic within 42 days of delivery were approached. Following informed consent and application of inclusion and exclusion criteria, 121 women delivered vaginally and 124 women delivered by CS were assessed using Mini International Neuropsychiatric Interview (MINI) and Pittsburgh Sleep Quality Index (PSQI). The data obtained were entered into MS Excel 2010 version and further analyzed using STATA v13. Both groups were matched on most demographic and clinical variables except age and whether pregnancy was planned or not. Postpartum depression was the most frequent diagnosis in both groups, with significantly more cases following CS compared to VD. Other psychiatric disorders were also found to be more following CS. The quality of sleep (QOS) was significantly poor following CS. QOS was significantly poor in the presence of a coexisting psychiatric disorder. This study has limitations in terms of being cross-sectional and disability being defined by cutoff scores on MINI and PSQI.

Abstract 11790: Behavioral Interviewing for Graduate Medical Education Programs in the Covid/Virtual Interviewing Era

Introduction: Coronavirus pandemic restrictions have affected social interactions, and the process of interviewing candidates for positions in graduate medical education (GME) programs is no exception. The threat of such restrictions is that candidates and programs may have less ability to achieve the best mutual fit. However, the pandemic also allows opportunities to rethink how we approach the interview process, and potentially optimize it. Behavioral interviewing (BI) techniques are one approach to both constructively address pandemic restrictions, and potentially improve recruitment to GME programs. Hypothesis: We hypothesized that behavioral interviewing could be integrated into a virtual interviewing process. Methods: We reviewed the behavioral interviewing process, and described how we integrated it into our virtual program recruitment of 91 candidates in 2020 and 2021. We elicited interviewer and interviewee feedback regarding the behavioral interviewing process, and analyzed discrepancies between ranks by traditional and behavioral interviewers. Results: Behavioral interviewing was viewed as highly positive or positive by 100% of interviewers and 93% of interviewees in 2021. The average discrepancy between standard and behavioral interview rank placement was 2.67 (SD 2); with 11 (8%) candidates exhibiting a significant rank divergence (> 5 rank orders). The best agreement between behavioral and traditional interviewer rank orders was in the top tertile of candidates. Conclusions: Behavioral interviewing can successfully be implemented in a virtual GME recruitment format, and provides opportunities to optimize program and candidate cohesion.

Stochastic Model to Characterize High-Frequency Ground Motion at Depth Validated by KiK-Net Vertical Array Data

ABSTRACTThe design of important structures for earthquake resistance requires an assessment of the local seismic hazard. One of its essential components is a site response that evaluates the amplification and attenuation of ground motion on a local scale. The shaking on the ground surface (in which it is generally measured) differs from the one at a depth; therefore, there is a need to characterize the ground motion at depth for important underground structures and buildings with deep foundations. In this study, we introduce a method to characterize the high-frequency (>1 Hz) ground motion at depth. The method makes use of a novel stochastic model (SM) that relates the ground motion at depth and on the surface in the Fourier domain. The SM is physics-based, its spectral amplification resembles an empirical 1D site response, and it allows reliable full-waveform ground-motion predictions. The method is validated through the comparison with empirical surface-to-borehole amplification curves observed in 144 selected KiK-net vertical arrays in Japan. Using a frequency range of 0.1–50 Hz, we identified 36 and 83 sites with a good and partially good mutual fit of theoretical and empirical amplification curves, respectively. Finally, we demonstrate the performance of the method in two diverse applications. First, we design a Bayesian inversion of the empirical surface-to-borehole amplification to retrieve the S-wave velocity model and an effective value of t* (the path-integrated effect of the quality factor). This inversion is applied to all selected KiK-net sites. Second, we perform a full-waveform prediction of the ground motion at depth from surface recordings of the 2018 northern Osaka Mw 5.6 earthquake. Both of these applications demonstrate a good performance of our SM in a broad frequency range.

Agile logic for SaaS implementation: Capitalizing on marketing automation software in a start-up

The emergence of Software-as-a-Service (SaaS) has facilitated agile technology implementation that focuses on iterative adaptations via learning by doing rather than the realization of a predesigned implementation plan. This study conceptualizes such an agile approach and explicates its operationalization via a four-year qualitative case study of a business-to-business (B2B) start-up firm’s implementation of a HubSpot marketing automation (MA) SaaS. The study shows how agile implementation continuously introduces adaptations to SaaS features and organizational routines for improving their mutual fit given the organization’s goals. The study also contributes to theory by offering a novel framework for managing agile implementation processes. The findings identify the key processes of sales lead management, content marketing, and customer intelligence through which start-up firms may capitalize on MA software.

Matching Perspectives of Refugees and Voluntary Sports Clubs in Germany

In recent years thousands of refugees from the Middle East and Africa have moved to Europe. Many of them have experienced extremely stressful events and suffer, amongst other things, from lack of social relationships. Policy makers do often convey the impression that voluntary sports clubs (VSCs) can easily help to deal with these issues, as they provide broad offers matching every person’s individual needs. With only few exceptions, research has focused on the view of VSCs and their officials, but mostly left out the perspectives of refugees themselves, especially those outside organized sports. Thus, the focus of the present contribution is on the mutual fit between refugees’ expectations and the offers that sports organizations have. Following a socio-ecological perspective, data from a research project will be used to illustrate both perspectives. Refugees were asked about hindering conditions for participating in sports. In addition, functionaries of sports organizations were asked to answer survey questions regarding the efforts that sports organizations make to include refugees. The results reveal that the majority of the refugees had already actively participated in sports offers in their countries of origin. After arriving in Germany, the sporting habits changed, mostly due to organizational and financial reasons. With respect to functionaries we found that the idea that sport is integrative per se is widely believed in the field.

Phytoremediation of cadmium contaminated soils by Amaranthus Hypochondriacus L.: The effects of soil properties highlighting cation exchange capacity

Phytoremediation is a cost-effective method to remedy Cd-contaminated soils. However, it is difficult to predict the performance of a given (hyper)accumulator at different soils due to the divergent plant-soil mutual fitness. Soil properties could be quite influential in determining plant growth and Cd uptake and therefore affect phytoremediation efficiency. To explore the primary soil factors that regulate the efficiency of phytoremediation, a phytoextraction experiment with grain amaranth (Amaranthus Hypochondriacus L.) was conducted in six long-term Cd-contaminated agricultural soils from southern China. The results showed that besides the soil available Cd, the soil cation exchange capacity (CEC) greatly affected plant growth and the amount of total Cd extraction. The deficiency of available Ca and Mg in low CEC soil caused insufficient uptake of Ca and Mg by grain amaranth, which was adverse to plant growth and Cd detoxification. The impaired plant biomass production sharply influenced plant total Cd accumulation, despite the relatively high Cd concentration in plants. While for the grain amaranth grown in soils with higher CEC, the increases in plant Ca and Mg promoted plant photosynthesis and plant tolerance to Cd stress, as indicated by the increase of leaf chlorophyll content and antioxidant enzyme activities, which contributed to the higher plant biomass and phytoremediation efficiency. These findings highlight that maintaining regular plant biomass production is vital to ensure the efficiency of phytoremediation, and low CEC of soil is a substantial barrier that needs to be concerned and further addressed for efficient phytoremediation of Cd-contaminated soils.

Direct identification of HMX via guest-induced fluorescence turn-on of molecular cage

Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is one of the most widely used powerful explosives. The direct and selective detection of HMX, without the requirement of specialized equipment, remains a great challenge due to its extremely low volatility, unfavorable reduction potential and lack of aromatic rings. Here, we report the first chemical probe of direct identification of HMX at ppb sensitivity based on a designed metal-organic cage (MOC). The cage features two unsaturated dicopper units and four electron donating amino groups inside the cavity, providing multiple binding sites to selectively enhance host-guest events. It was found that compared to other explosive molecules the capture of HMX inside the cavity would strongly modulate the emissive behavior of the host cage, resulting in highly induced fluorescence “turn-on” (160 folds). Based on the density functional theory (DFT) simulation, the mutual fit of both size and binding sites between host and guest leads to the synergistic effects that perturb the ligand-to-metal charge-transfer (LMCT) process, which is probably the origin of such selective HMX-induced turn-on behavior.

Wolbachia spreading dynamics in Nilaparvata lugens with two strains

The Nilaparvata lugens is primary vector of rice diseases such as rice ragged stunt. A recent study reported the Wolbachia wStri can cause the cytoplasmic incompatibility of N.lugens, and inhibit the infection and transmission of rice ragged stunt virus in the laboratory. In this work, based on multi-strains infection mechanisms including incomplete cytoplasmic incompatibility and imperfect maternal transmission, we use differential equations to describe the spreading dynamics of Wolbachia wStri and wLug in N.lugens population. The system can exhibit one or two stable equilibria. The stability of equilibrium infected with wStri shows that wStri can invade wild populations when the cytoplasmic incompatibility intensity of wStri and the maternal inheritance leakage rate of wLug are higher than some certain thresholds. The stability conditions of the equilibria are related to the mutual fitness of the populations. If one population is more adaptable than the other, it will be in the ascendancy. An initial value region is found, from which the trajectory of system tends to the equilibrium infected with wStri. Studies on subsystem without wStri demonstrate there is a symbiotic relation between Wolbachia wLug and N.lugens population, and Wolbachia wLug can promote the reproduction of N.lugens. In addition, our numerical results are consistent with relevant literatures experimental results. Our results can guide the release of N.lugens infected with wStri in rice fields to control the growth of wild N.lugens population.

에너지전환 정책 홍보 메시지 프레이밍이 정책 지지도에 미치는 영향 연구 : 프레이밍과 해석수준의 상호 적합성 탐색을 중심으로

에너지전환 정책 홍보 메시지 프레이밍이 정책 지지도에 미치는 영향 연구 : 프레이밍과 해석수준의 상호 적합성 탐색을 중심으로

Evaluation of phytoremediation potential of five Cd (hyper)accumulators in two Cd contaminated soils

A phytoextraction experiment with five Cd hyperaccumulators (Amaranthus hypochondriacus, Celosia argentea, Solanum nigrum, Phytolacca acinosa and Sedum plumbizincicola) was conducted in two soils with different soil pH (5.93 and 7.43, respectively). Most accumulator plants grew better in the acidic soil, with 19.59–39.63% higher biomass than in the alkaline soil, except for S. plumbizincicola. The potential for a metal-contaminated soil to be cleaned up using phytoremediation is determined by the metal uptake capacity of hyperaccumulator, soil properties, and mutual fitness of plant-soil relationships. In the acidic soil, C. argentea and A. hypochondriacus extracted the highest amount of Cd (1.03 mg pot−1 and 0.92 mg pot−1, respectively). In the alkaline soil, S. plumbizincicola performed best, mainly as a result of high Cd accumulation in plant tissue (541.36 mg kg−1). Most plants achieved leaf Cd bioconcentration factor (BCF) of >10 in the acidic soil, compared to <4 in the alkaline soil. Soil Cd availability was chiefly responsible for such contrasting metal extraction capacity, with 5.02% fraction and 48.50% fraction of total Cd being available in the alkaline and acidic soil, respectively. In the alkaline soil, plants tended to increase rhizosphere soil available Cd mainly through excreting more low molecular weight organic acids, not through changing the soil pH. In the acidic soil, plants slightly decreased soil available Cd. Those species which have high Ca, Zn, Fe uptake capacity extract more Cd from soil, and a positive correlation was found between the concentrations of Cd and Ca, Zn, Fe in leaves. Soil available Ca2+, Mg2+, SO42−, Cl− did not play a key role in Cd uptake by plants. In summary, acidic soil was of higher potential to recover from Cd contamination by phytoextraction, while in the alkaline soil, S. plumbizincicola showed potential for Cd phytoextraction.

Semiotic Fitting and the Nativeness of Community

The concept of ‘semiotic fitting’ is what we provide as a model for the description and analysis of the diversity dynamics and nativeness in semiotic systems. One of its sources is the concept of ‘ecological fitting’ which was introduced by Daniel Janzen as the mechanism for the explanation of diversity in tropical ecosystems and which has been shown to work widely over the communities of various types. As different from the neo-Darwinian concept of fitness that describes reproductive success, ‘fitting’ describes functional (sign) relations and aboutness. Diversity of a semiotic system is strongly dependent on the mutual fitting of agents of which the semiotic system consists. The focus on semiotic fitting means that, in the analysis of diversity, we pay particular attention to decision making (choice), functional plasticity, recognition windows, the depth of interpretation of the agents, and the categories responsible for the structure of the semiotic system. The concept of semiotic fitting has an early analogue in Jakob von Uexkull’s concept of ‘Einpassung’ (as different from ‘Anpassung’, meaning ‘evolutionary adaptation’). The close concepts of ‘semiotic fitness’, introduced by Jesper Hoffmeyer and by Stephanie Walsh Matthews, ‘semiotic selection’, introduced by Timo Maran and Karel Kleisner, and ‘semiotic niche’, introduced by Hoffmeyer, provide different versions of the same model. If community is constructing itself on the basis of (relational) fitting, then nativeness of the community is a product of fitting, not vice versa. Nativeness is a feature that deepens in the course of community succession. The concept of ‘semiotic fitting’ demonstrates the possibility to analyse the role of both indigenous and alien species or other agents in a community on the basis of a single model.

Using maternal rescue of pups in a cup to investigate mother-infant interactions in mice/rodents

Efficient parental care is indispensable for survival of the mammalian offspring, and therefore both parents and offspring cooperate to achieve the best performance. For example, when parents transport altricial offspring, the offspring immediately respond by reducing its cry and movement in both human infants and rodent pups. This coordinated set of central, motor and cardiac responses is designated as the Transport Response (TR) and is shown to facilitate maternal carrying in rodents. The present study aims to investigate the core behavioural characteristics of mother-infant interaction, and to investigate the mechanisms underlying the mother-pup cooperation using pharmacological and genetic manipulations (i.e. Oprm1-/). Along with the clear developmental changes of the pups' immobility and posture during maternal carrying as previously reported, there were also adaptations in maternal strategies, particularly in positioning of foothold and oral grasp over the pup's body, with the pups' age and pup's behaviour. Tree-based models elucidated that both of these maternal variables as well as percentage of pups' struggle predict the time required for pup retrieval from a cup. When the sensory-motor control in pups was disturbed by pharmacological or genetic manipulations, these core behaviours were inefficiently performed and impede maternal retrieval. Mother-infant mutual fit is a complex construct where several intermingled mechanisms are involved. Thus mothers and infants, when interacting, should be considered together as one whole system in which any change in one side or the other, affects the output of the whole dyad. The outcome of the interaction relays on a specific dynamic pattern of infant and maternal behaviours, which mutually change and adapt to fit each other's needs. Key features to reach a successful outcome of the interaction were the maternal retrieving strategy and infants’ Transport Response behaviour.

Interactions between oil-collecting bees and Krameria grandiflora (Krameriaceae) with emphasis on the role of specialized floral traits in the mutual fit

Oil-producing flowers have evolved specialized traits along with the ability to secrete oil as reward, leading to the expectation of a narrow relationship between floral architecture and oil-collecting behaviours of pollinators. Krameriaceae flowers have a showy calyx and a less conspicuous dimorphic corolla modified into a pair of elaiophores that secrete the oil, and a group of petaloid petals that, among oil-collecting bees, are used by only Centris (Centridini) during the oil gathering. A manipulative experiment consisted of excising these floral parts to test the prediction that these structures contribute to successful oil gathering by the bees and plant reproduction. We surveyed the oil-collecting bees associated with the Krameria grandiflora A. St.-Hil. across its distribution range and performed the experiment in populations associated with two different oil-collecting bee taxa—Caenonomada (Tapinotaspidini) and Centris, the main pollinators. Although predicted to mediate the floral mechanical fit with Centris, the absence of the petaloid petals had a neutral effect on both oil-gathering behaviour and seed set, when comparing Caenonomada and Centris. A negative effect on these responses was found when the elaiophores were excised, indicating that these glands have greater importance than the petals related to the mutual fit between flowers and pollinators. However, the petaloid petals seemed to function jointly with the sepals in pollinator attraction. When the sepals were excised, only Centris behaviour was affected, but not that of Caenonomada, indicating potentially divergent selective pressures on the calyx. In addition, we provide a novel oil host plant for several oil-collecting bees.

Root Mean Square Minimum Distance as a Quality Metric for Stochastic Optical Localization Nanoscopy Images

A localization algorithm in stochastic optical localization nanoscopy plays an important role in obtaining a high-quality image. A universal and objective metric is crucial and necessary to evaluate qualities of nanoscopy images and performances of localization algorithms. In this paper, we propose root mean square minimum distance (RMSMD) as a quality metric for localization nanoscopy images. RMSMD measures an average, local, and mutual fitness between two sets of points. Its properties common to a distance metric as well as unique to itself are presented. The ambiguity, discontinuity, and inappropriateness of the metrics of accuracy, precision, recall, and Jaccard index, which are currently used in the literature, are analyzed. A numerical example demonstrates the advantages of RMSMD over the four existing metrics that fail to distinguish qualities of different nanoscopy images in certain conditions. The unbiased Gaussian estimator that achieves the Fisher information and Cramer-Rao lower bound (CRLB) of a single data frame is proposed to benchmark the quality of localization nanoscopy images and the performance of localization algorithms. The information-achieving estimator is simulated in an example and the result demonstrates the superior sensitivity of RMSMD over the other four metrics. As a universal and objective metric, RMSMD can be broadly employed in various applications to measure the mutual fitness of two sets of points.