Some results on likelihood ratios for two-parameter processes

Several years ago a three-parameter system of stellar classification has been proposed (1, 2), for the early-type stars (O-G): it was an improvement on the two-parameter system described by Barbier and Chalonge (3).

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Sentence Repetition: A Clinical Marker for Developmental Language Disorder in Danish

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-l-18-0327 ◽

2019 ◽

Vol 62 (12) ◽

pp. 4450-4463

Author(s):

Rikke Vang Christensen

Keyword(s):

Language Disorder ◽

Future Research ◽

Typically Developing ◽

Developmental Language Disorder ◽

Older Children ◽

Likelihood Ratios ◽

Clinical Marker ◽

Sentence Repetition ◽

Good Identification ◽

Syntactic Properties

Purpose The aim of the study was to explore the potential of performance on a Danish sentence repetition (SR) task—including specific morphological and syntactic properties—to identify difficulties in children with developmental language disorder (DLD) relative to typically developing (TD) children. Furthermore, the potential of the task as a clinical marker for Danish DLD was explored. Method SR performance of children with DLD aged 5;10–14;1 (years;months; n = 27) and TD children aged 5;3–13;4 ( n = 87) was investigated. Results Compared to TD same-age peers, children with DLD were less likely to repeat the sentences accurately but more likely to make ungrammatical errors with respect to verb inflection and use of determiners and personal pronouns. Younger children with DLD also produced more word order errors that their TD peers. Furthermore, older children with DLD performed less accurately than younger TD peers, indicating that the SR task taps into morphosyntactic areas of particular difficulty for Danish children with DLD. The classification accuracy associated with SR performance showed high levels of sensitivity and specificity (> 90%) and likelihood ratios indicating good identification potential for clinical and future research purposes. Conclusion SR performance has a strong potential for identifying children with DLD, also in Danish, and with a carefully designed SR task, performance has potential for revealing morphosyntactic difficulties. Supplemental Material https://doi.org/10.23641/asha.10314437

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Clausal Density Between Ages 4 and 9 Years for the Edmonton Narrative Norms Instrument: Reference Data and Psychometric Properties

Language Speech and Hearing Services in Schools ◽

10.1044/2020_lshss-20-00043 ◽

2020 ◽

pp. 1-15

Author(s):

Ling-Yu Guo ◽

Phyllis Schneider ◽

William Harrison

Keyword(s):

Diagnostic Accuracy ◽

Psychometric Properties ◽

Language Impairment ◽

Reference Data ◽

Reliability And Validity ◽

Correlation Coefficients ◽

Criterion Validity ◽

Likelihood Ratios ◽

Generation Task ◽

Sensitivity Specificity

Purpose This study provided reference data and examined psychometric properties for clausal density (CD; i.e., number of clauses per utterance) in children between ages 4 and 9 years from the database of the Edmonton Narrative Norms Instrument (ENNI). Method Participants in the ENNI database included 300 children with typical language (TL) and 77 children with language impairment (LI) between the ages of 4;0 (years;months) and 9;11. Narrative samples were collected using a story generation task, in which children were asked to tell stories based on six picture sequences. CD was computed from the narrative samples. The split-half reliability, concurrent criterion validity, and diagnostic accuracy were evaluated for CD by age. Results CD scores increased significantly between ages 4 and 9 years in children with TL and those with LI. Children with TL produced higher CD scores than those with LI at each age level. In addition, the correlation coefficients for the split-half reliability and concurrent criterion validity of CD scores were all significant at each age level, with the magnitude ranging from small to large. The diagnostic accuracy of CD scores, as revealed by sensitivity, specificity, and likelihood ratios, was poor. Conclusions The finding on diagnostic accuracy did not support the use of CD for identifying children with LI between ages 4 and 9 years. However, given the attested reliability and validity for CD, reference data of CD from the ENNI database can be used for evaluating children's difficulties with complex syntax and monitoring their change over time. Supplemental Material https://doi.org/10.23641/asha.13172129

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Subjective Time Preference and Willingness to Pay for an Energy-Saving Durable Good

Zeitschrift für Sozialpsychologie ◽

10.1024//0044-3514.32.3.133 ◽

2001 ◽

Vol 32 (3) ◽

pp. 133-141 ◽

Cited By ~ 4

Author(s):

Gerrit Antonides ◽

Sophia R. Wunderink

Keyword(s):

Willingness To Pay ◽

Energy Saving ◽

Subjective Time ◽

Durable Good ◽

Discount Function ◽

Hyperbolic Discount ◽

The One ◽

Two Parameter ◽

Difference Effect ◽

Better Than

Summary: Different shapes of individual subjective discount functions were compared using real measures of willingness to accept future monetary outcomes in an experiment. The two-parameter hyperbolic discount function described the data better than three alternative one-parameter discount functions. However, the hyperbolic discount functions did not explain the common difference effect better than the classical discount function. Discount functions were also estimated from survey data of Dutch households who reported their willingness to postpone positive and negative amounts. Future positive amounts were discounted more than future negative amounts and smaller amounts were discounted more than larger amounts. Furthermore, younger people discounted more than older people. Finally, discount functions were used in explaining consumers' willingness to pay for an energy-saving durable good. In this case, the two-parameter discount model could not be estimated and the one-parameter models did not differ significantly in explaining the data.

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Diagnostic accuracy of magnetic resonance angiography for acute pulmonary embolism - a systematic review and meta-analysis

VASA ◽

10.1024/0301-1526/a000509 ◽

2016 ◽

Vol 45 (2) ◽

pp. 149-154 ◽

Cited By ~ 2

Author(s):

Jie Li ◽

Lei Feng ◽

Jiangbo Li ◽

Jian Tang

Keyword(s):

Pulmonary Embolism ◽

Magnetic Resonance ◽

Magnetic Resonance Angiography ◽

Diagnostic Accuracy ◽

Acute Pulmonary Embolism ◽

Meta Analysis ◽

Likelihood Ratios ◽

Summary Receiver Operating Characteristic ◽

Acute Pe ◽

Limited Sensitivity

Abstract. Background: The aim of this meta-analysis was to evaluate the diagnostic accuracy of magnetic resonance angiography (MRA) for acute pulmonary embolism (PE). Methods: A systematic literature search was conducted that included studies from January 2000 to August 2015 using the electronic databases PubMed, Embase and Springer link. The summary receiver operating characteristic (SROC) curve, sensitivity, specificity, positive likelihood ratios (PLR), negative likelihood ratios (NLR), and diagnostic odds ratio (DOR) as well as the 95 % confidence intervals (CIs) were calculated to evaluate the diagnostic accuracy of MRA for acute PE. Meta-disc software version 1.4 was used to analyze the data. Results: Five studies were included in this meta-analysis. The pooled sensitivity (86 %, 95 % CI: 81 % to 90 %) and specificity (99 %, 95 % CI: 98 % to 100 %) demonstrated that MRA diagnosis had limited sensitivity and high specificity in the detection of acute PE. The pooled estimate of PLR (41.64, 95 % CI: 17.97 to 96.48) and NLR (0.17, 95 % CI: 0.11 to 0.27) provided evidence for the low missed diagnosis and misdiagnosis rates of MRA for acute PE. The high diagnostic accuracy of MRA for acute PE was demonstrated by the overall DOR (456.51, 95 % CI: 178.38 - 1168.31) and SROC curves (AUC = 0.9902 ± 0.0061). Conclusions: MRA can be used for the diagnosis of acute PE. However, due to limited sensitivity, MRA cannot be used as a stand-alone test to exclude acute PE.

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