The Oligochaeta forms an important part of the macroinvertebrates inhabiting sediments of lotic ecosystems. It has an important role in the cycling of matter and energy transfer in these environments. The aim of this study is to analyse limnological variables, their influence on the structure and diversity of benthic oligochaete taxocenosis in a stretch of the Upper São Francisco River and its ...

When using functional brain imaging to study neuropsychiatric patients an important challenge is determining whether the imaging task assesses individual differences with equal precision in healthy control and impaired patient groups. Classical test theory (CTT) requires separate reliability studies of patients and controls to determine equivalent measurement precision with additional studies t...

Evaluation of NLP methods requires testing against a previously vetted gold-standard test set and reporting standard metrics (accuracy/precision/recall/F1). The current assumption is that all items in a given test set are equal with regards to difficulty and discriminating power. We propose Item Response Theory (IRT) from psychometrics as an alternative means for gold-standard test-set generati...

Despite the well-known theoretical differences between item response theory (IRT) and classical test theory (CTT), research examining their empirical properties has failed to reveal consistent, demonstrable differences due to usage of samples with errors, incorrect assumptions & incorrect calculations. Dr. Natarajan (India, 1984) had proved the item invariance with his classic 20 X 76 test data...

This research aims at exploring the critical success factors in addition to the captured benefits and value with regard to the use and deployment of Iris Recognition Technology (IRT) in the banking industry. We discuss the traditional practices of information security models in the banking sector and how these models have been significantly improved by the use of biometrics and more specificall...

Information Systems (IS) research frequently uses survey data to measure the interplay between technological systems and human beings. Researchers have developed sophisticated procedures to build and validate multi-item scales that measure latent constructs. Most studies use classical test theory (CTT), which suffers from several theoretical shortcomings. We discuss these problems and present i...

BACKGROUND Performance on psychometric tests is key to diagnosis and monitoring treatment of dementia. Results are often reported as a total score, but there is additional information in individual items of tests which vary in their difficulty and discriminatory value. Item difficulty refers to an ability level at which the probability of responding correctly is 50%. Discrimination is an index ...

Item response theory (IRT) is an important method of assessing the validity of measurement scales that is underutilized in the field of psychiatry. IRT describes the relationship between a latent trait (e.g., the construct that the scale proposes to assess), the properties of the items in the scale, and respondents' answers to the individual items. This paper introduces the basic premise, assum...