Error rates and variation between observers are reduced with the use of photographic matching software for capture-recapture studies

2017 ◽  
Vol 38 (3) ◽  
pp. 315-325 ◽  
Author(s):  
Sam S. Cruickshank ◽  
Benedikt R. Schmidt
Keyword(s):  
Individual Recognition ◽  
Computer Software ◽  
Rejection Rate ◽  
Error Rates ◽  
Small Error ◽  
Matching Accuracy ◽  
Bombina Variegata ◽  
Capture Recapture ◽  
False Rejection

Photographic capture-mark-recapture (CMR) permits individual recognition whilst avoiding many of the concerns involved with marking animals. However, the construction of capture histories from photographs is a time-consuming process. Furthermore, matching accuracy is determined based on subjective judgements of the person carrying out the matching, which can lead to errors in the resulting datasets – particularly in long-term projects where multiple observers match images. We asked 63 volunteers to carry out two photographic-matching exercises using a database of known individuals of the yellow-bellied toad (Bombina variegata). From these exercises, we quantified the matching accuracy of volunteers in terms of false-acceptance and false-rejection rates. Not only were error rates greatly reduced with the use of photographic-matching software, but variation in error rates among volunteers was also lowered. Furthermore, the use of matching software led to substantial increases in matching speeds and an 87% reduction in the false-rejection rate. As even small error rates have the potential to bias CMR analyses, these results suggest that computer software could substantially reduce errors in CMR datasets. The time-savings and reduction in variance among observers suggest that such methods could be particularly beneficial in long-term CMR projects where a large number of images may be matched by multiple observers.

Can ventral pattern be used for individual recognition of the vulnerable Pyrenean brook newt (Calotriton asper)?

2021 ◽  
pp. 99-110
Author(s):  
Manon Dalibard
Keyword(s):  
Individual Recognition ◽  
Rejection Rate ◽  
Poor Quality ◽  
Error Rates ◽  
Acceptance Rate ◽  
Computer Assisted ◽  
Photo Identification ◽  
Passive Integrated Transponders ◽  
Reference Images ◽  
Colour Patterns

Individual recognition of animal species is a prerequisite for capture-mark-recapture (CMR) studies. For amphibians, photoidentification of body pattern is a non-invasive and less expensive alternative than classical marking methods (e.g. passive integrated transponder). However, photo-identification is effective only if the patterns are (i) sufficiently variable between individuals, and (ii) stable over time. This method also depends on the observer’s judgment. In the present study, we assessed the effectiveness of an automatic algorithm (AmphIdent) to recognise ventral colour patterns of the Pyrenean brook newt (Calotrion asper), endemic to the Pyrenees Mountains of France. To assess the performance of the tested method, 113 individuals from two different streams were marked with passive integrated transponders (PIT-tags). We used false rejection rate (FRR), false acceptance rate (FAR) and true acceptance rate (TAR) as metrics to evaluate performances of photoidentification. Mean FRR was 7.3 %, FAR was 5.2 %, and TAR was 92 % across both streams, both sexes and all the observers. FAR was significantly different between sexes, while FRR and TAR were significantly influenced by the interaction between the sex and the stream. Despite these differences, our error rates are among the lowest values found in the literature for both amphibian and non-amphibian computer-assisted photo-identification. We found that poor-quality reference pictures could lead to an increasing difficulty to achieve a correct match when time since first capture rose. Consequently, individual photo-identification using AmphIdent software is a reliable tool to aid in the monitoring the Pyrenean brook newts, provided that pictures are taken with care, reference images are regularly updated and observers are properly trained to use the software and interpret images.

Image Matching Application Based on Modified SURF Algorithm

2013 ◽  
Vol 423-426 ◽  
pp. 2591-2596
Author(s):  
Zhen Yuan Ma ◽  
Shi Xu Shi ◽  
Li Xian Yuan ◽  
Pei Chang Gu ◽  
Han Huang
Keyword(s):  
Critical Points ◽  
Image Matching ◽  
High Performance ◽  
Rejection Rate ◽  
Detection Algorithm ◽  
Test Paper ◽  
Matching Accuracy ◽  
False Rejection Rate ◽  
Modified Algorithm ◽  
False Rejection

The key technique to increase the accuracy of electronic marking is the technique of image matching, namely to match two doubtfully duplicate images. Currently there are few technologies aiming for features on test paper images with high performance on matching accuracy. The research is based on SURF algorithm and specific to the features of test paper images. Thus the research is to put forward the modified algorithm with constraints among feature spots of orientation angles on their geometrical positions, including differential constraints on critical points from approximate blank test papers with less individual features at the same time. After processing and analyzing 2,000 test paper gathered from one actual examination, the results show that the modified detection algorithm has 100% false rejection rate and 100% accuracy when it is used to detect the test paper matching.

scholarly journals Population position along the fast-slow life-history continuum predicts intraspecific variation in actuarial senescence

2019 ◽  
Author(s):  
Hugo Cayuela ◽  
Jean-François Lemaître ◽  
Eric Bonnaire ◽  
Julian Pichenot ◽  
Benedikt R. Schmidt
Keyword(s):  
Life History ◽  
Intraspecific Variation ◽  
Population Variation ◽  
Life History Strategies ◽  
Wild Populations ◽  
Captive Populations ◽  
Bombina Variegata ◽  
In The Wild ◽  
Capture Recapture

AbstractPatterns of actuarial senescence can be highly variable among species. Previous comparative analyses revealed that both age at the onset of senescence and rates of senescence are linked to the species’ position along the fast-slow life-history continuum. As there are few long-term datasets of wild populations with known-age individuals, intraspecific (i.e. between-population) variation in senescence is understudied and limited to comparisons of wild and captive populations of the same species, mostly birds and mammals. In this paper, we examined how population position along the fast-slow life history continuum affects senescence patterns in an amphibian, Bombina variegata. We used capture-recapture data collected in four populations with contrasted life history strategies. Senescence trajectories were drawn using Bayesian capture-recapture models. We show that in “slow” populations the onset of senescence was earlier and individuals aged at a faster rate than individuals in “fast” populations. Our study provides one of the few empirical examples of between-population variation in senescence patterns in the wild and confirms that the fast-slow life history gradient is associated with both macroevolutionary and microevolutionary patterns of senescence.

Effects of individual misidentification on estimates of survival in long-term mark–resight studies

The Condor ◽  
2019 ◽  
Vol 121 (1) ◽  
Author(s):  
Anna M Tucker ◽  
Conor P McGowan ◽  
Robert A Robinson ◽  
Jacquie A Clark ◽  
James E Lyons ◽  
...  
Keyword(s):  
Simulation Study ◽  
Study Data ◽  
Error Rates ◽  
Data Filtering ◽  
Single Observation ◽  
Demographic Rates ◽  
Survival Estimation ◽  
Capture Recapture

Abstract All ecological measurements are subject to error; the effects of missed detection (false negatives) are well known, but the effects of mistaken detection (false positives) are less understood. Long-term capture–recapture datasets provide valuable ecological insights and baselines for conservation and management, but where such studies rely on noninvasive re-encounters, such as field-readable color bands, there is the potential to accumulate detection errors as the length of the study and number of tags deployed increases. We investigated the prevalence and effects of misreads in a 10-yr dataset of Red Knots (Calidris canutus rufa) marked with field-readable leg flags in Delaware, USA. We quantified the effects of misreads on survival estimation via a simulation study and evaluated whether removal of individuals only reported once in a year (potential misreads) influenced survival estimation from both simulated datasets and our case study data. We found overall apparent error rates of 0.31% (minimum) to 6.6% (maximum). Observer-specific error rates and the variation among observers both decreased with the number of flags an observer recorded. Our simulation study showed that misreads lead to spurious negative trends in survival over time, particularly for long-term studies. Removing all records in which a flag was only recorded once in a sampling occasion reduced bias and eliminated spurious negative trends in survival but also reduced precision in survival estimates. Without data filtering, we found a slight decrease in Red Knot annual survival probability from 2008 to 2018 (β = −0.043 ± 0.03), but removing all single-observation records resulted in no apparent trend (β = −0.0074 ± 0.02). Spurious trends in demographic rates could influence inference about population trajectories and resultant conservation decision-making. Data filtering could eliminate errors, but researchers should carefully consider the tradeoff between precision obtained by larger sample sizes and potential bias due to misreads in their data.

scholarly journals Leopard Density Estimation within an Enclosed Reserve, Namibia Using Spatially Explicit Capture-Recapture Models

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 724
Author(s):  
Noack ◽  
Heyns ◽  
Rodenwoldt ◽  
Edwards
Keyword(s):  
Management Strategies ◽  
Camera Traps ◽  
Spatially Explicit ◽  
Conservation Areas ◽  
Term Survival ◽  
New Class ◽  
Capture Recapture ◽  
Wildlife Populations ◽  
Effective Conservation

The establishment of enclosed conservation areas are claimed to be the driving force for the long-term survival of wildlife populations. Whilst fencing provides an important tool in conservation, it simultaneously represents a controversial matter as it stops natural migration processes, which could ultimately lead to inbreeding, a decline in genetic diversity and local extinction if not managed correctly. Thus, wildlife residing in enclosed reserves requires effective conservation and management strategies, which are strongly reliant on robust population estimates. Here, we used camera traps combined with the relatively new class of spatially explicit capture-recaptured models (SECR) to produce the first reliable leopard population estimate for an enclosed reserve in Namibia. Leopard density was estimated at 14.51 leopards/100 km2, the highest recorded density in Namibia to date. A combination of high prey abundance, the absence of human persecution and a lack of top-down control are believed to be the main drivers of the recorded high leopard population. Our results add to the growing body of literature which suggests enclosed reserves have the potential to harbour high densities and highlight the importance of such reserves for the survival of threatened species in the future.

National survey on appropriateness of clinical biochemistry reporting in China

2015 ◽  
Vol 53 (11) ◽  
Author(s):  
Fengfeng Kang ◽  
Wei Wang ◽  
Zhiguo Wang
Keyword(s):  
Quality Indicators ◽  
National Survey ◽  
Clinical Biochemistry ◽  
Error Rates ◽  
Significant Difference ◽  
Survey Results ◽  
Complete Report ◽  
Term Monitoring ◽  
Reliable Testing

AbstractAccurate and reliable testing reports play an important role in the prevention, diagnosis, treatment and prognosis of disease. However, little is known about the appropriateness of laboratory testing reporting in China. This national survey takes clinical biochemistry as an example to investigate the state of reporting appropriateness in our country.An electronic questionnaire was sent to 1209 laboratories. The participants were asked to retrospectively evaluate the error rates of the following quality indicators: report template integrity, report content filling integrity, report delay, report recall, non-conformities between instrument and laboratory information system (LIS) data, non-conformities between report and request, report notification error, and report modification. Mann-Whitney and Kruskal-Wallis tests were used to identify the potential impacts of reporting appropriateness.A total of 662 of the 1209 laboratories (55%) submitted the survey results, with three returning incomplete data. For the integrity of the report, only 31% of the laboratories had a complete report template that contained all of 21 elements. In addition, the overall error rate of content filling integrity was 45.9% for 19,770 pieces of reports. The overall σ-values of other six quality indicators were all >4, and no significant difference was found among different departments. Group comparison suggested that reporting electronically had a better performance.The laboratory reporting system in China needs to improve, particularly the integrity of the report. Strengthening information technology will not only promote reporting appropriateness, but also guarantee accurate, standardized and traceable data collection and long-term monitoring.

Short Communication: Estimating abundance, survival and age structure of the Alberes cattle using recapture techniques

2011 ◽  
Vol 91 (3) ◽  
pp. 343-347
Author(s):  
Marta Fina ◽  
Joaquim Casellas ◽  
Jesús Piedrafita
Keyword(s):  
Overall Survival ◽  
Genetic Variability ◽  
Age Structure ◽  
Death Rate ◽  
Short Communication ◽  
Average Length ◽  
Local Breed ◽  
Capture Recapture ◽  
Average Longevity

Fina, M., Casellas, J. and Piedrafita, J. 2011. Short Communication: Estimating abundance, survival and age structure of the Alberes cattle using recapture techniques. Can. J. Anim. Sci. 91: 343–347. The Alberes breed is an endangered bovine breed with an unknown population size. In this study, we estimated a total of 447.9 (435.5 to 456.6) individuals using capture-recapture methods. Overall survival and recapture estimates were 0.85±0.01 and 0.94±0.01, respectively, leading to an average longevity of 5.64 yr and with the highest death rate concentrated in the first 3 yr of life (38.94%). For breeding cows, the average length of the productive life was 8.35 yr. The current population of this local breed is too small to prevent future losses of genetic variability, and a conservation program is essential to ensure the long-term viability of the breed.

scholarly journals Variance component analysis of body mass in a wild population of deer (Odocoileus virginianus): results from two decades of research

2013 ◽  
Vol 40 (7) ◽  
pp. 588 ◽  
Author(s):  
Stephen L. Webb ◽  
Kenneth L. Gee ◽  
Randy W. DeYoung ◽  
Seth M. Harju
Keyword(s):  
Odocoileus Virginianus ◽  
Body Mass ◽  
Environmental Effects ◽  
Phenotypic Traits ◽  
Phenotypic Variance ◽  
Components Of Variance ◽  
Habitat Improvement ◽  
Capture Recapture ◽  
Sources Of Variation

Context Long-term studies of large, vertebrate mammals using capture–recapture data are scarce, even though long-term ecological studies are requisite to understanding quantitative genetics and evolutionary processes that can be applied as part of management programs. Aims Objectives were to (1) partition components of variation in body mass to understand the differential effects of environmental variation on the sexes during ontogeny, to better prescribe habitat-improvement projects, and (2) estimate repeatability to assess potential for selection on body mass. Methods We used a 23-year dataset (1983–2005) of capture–recapture records of wild white-tailed deer (Odocoileus virginianus) to estimate components of variance and repeatability of body mass. We used an animal-model approach that employed the use of general linear mixed models and restricted maximum likelihood to adjust for the effects of age (i.e. fixed effect), and to partition the total phenotypic variance into among-individual (i.e. the deer), permanent environmental (i.e. year of birth) and temporary environmental (i.e. year of measurement and residual) effects (all modelled as random effects). Key results We found that body mass increased with age in both sexes, repeatability of body mass was 0.595 for females and 0.716 for males, and among-individual variation was more influential on body mass than were permanent and temporary environmental effects combined. Year of birth was more important in males than females, but changed during the course of ontogeny for both sexes. Year of measurement did not influence post-rut body mass in males, but did contribute to variation in body mass of females. Conclusions These long-term data offer insights into the sources of variation that influence body mass of deer, which can be used to understand how environmental sources of variation influence phenotypic traits, and for developing management plans and making selection decisions. Implications Knowledge of repeatability (as an upper limit to heritability) can be used to make management decisions related to selection, culling and breeding, whereas understanding environmental effects can lead to better management recommendations (e.g. habitat-improvement projects).

scholarly journals Factors Welfare Recipients View Significant to Become Self-Sufficient

2017 ◽  
Vol 12 (11) ◽  
pp. 1
Author(s):  
Lucson Francois
Keyword(s):  
Community Service ◽  
Vocational Training ◽  
Computer Software ◽  
Welfare Recipients ◽  
Housing Assistance ◽  
Policy Makers ◽  
Social Work Research ◽  
The Government ◽  
Depth Interviews

The purpose of this study was to explore the perceptions of welfare recipients regarding factors significant to becoming self-sufficient in Southeast Florida. The study took a qualitative approach, administering in-depth interviews to 20 current welfare clients. To ensure valid and reliable results, a computer software program known as QSR NVivo 10 was utilized for the accurate coding of responses. Findings in the study suggest that benefits, such as child care, transportation, Medicaid, subsidized employment, housing assistance, and vocational training provided by the government are significant in helping welfare recipients successfully transition from relying on the governmental assistance to obtaining reliable employment with the ultimate goal of becoming self-sufficient; however, their perception differs from policy makers in terms of the benefits provided by the government and how those benefits should be provided. Participants reported that the most helpful programs to their becoming successful were subsidized employment and vocational training. They believed the programs should be redesigned to focus on clients’ success. They believed community service did not help them achieve their long- term goal of becoming independent. Implications for social work research and practice are suggested.

scholarly journals Effect of vocabulary mapping for conditions on phenotype cohorts

2018 ◽  
Vol 25 (12) ◽  
pp. 1618-1625 ◽  
Author(s):  
George Hripcsak ◽  
Matthew E Levine ◽  
Ning Shang ◽  
Patrick B Ryan
Keyword(s):  
Knowledge Engineering ◽  
Total Error ◽  
False Negative ◽  
International Classification Of Diseases ◽  
Error Rates ◽  
Small Error ◽  
Snomed Ct ◽  
Order Of Magnitude ◽  
Systematized Nomenclature Of Medicine ◽  
Gold Standards

Abstract Objective To study the effect on patient cohorts of mapping condition (diagnosis) codes from source billing vocabularies to a clinical vocabulary. Materials and Methods Nine International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9-CM) concept sets were extracted from eMERGE network phenotypes, translated to Systematized Nomenclature of Medicine - Clinical Terms concept sets, and applied to patient data that were mapped from source ICD9-CM and ICD10-CM codes to Systematized Nomenclature of Medicine - Clinical Terms codes using Observational Health Data Sciences and Informatics (OHDSI) Observational Medical Outcomes Partnership (OMOP) vocabulary mappings. The original ICD9-CM concept set and a concept set extended to ICD10-CM were used to create patient cohorts that served as gold standards. Results Four phenotype concept sets were able to be translated to Systematized Nomenclature of Medicine - Clinical Terms without ambiguities and were able to perform perfectly with respect to the gold standards. The other 5 lost performance when 2 or more ICD9-CM or ICD10-CM codes mapped to the same Systematized Nomenclature of Medicine - Clinical Terms code. The patient cohorts had a total error (false positive and false negative) of up to 0.15% compared to querying ICD9-CM source data and up to 0.26% compared to querying ICD9-CM and ICD10-CM data. Knowledge engineering was required to produce that performance; simple automated methods to generate concept sets had errors up to 10% (one outlier at 250%). Discussion The translation of data from source vocabularies to Systematized Nomenclature of Medicine - Clinical Terms (SNOMED CT) resulted in very small error rates that were an order of magnitude smaller than other error sources. Conclusion It appears possible to map diagnoses from disparate vocabularies to a single clinical vocabulary and carry out research using a single set of definitions, thus improving efficiency and transportability of research.

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