Likelihood ratios for time-continuous data models: The white noise approach

Multifractional Brownian motion is a Gaussian process which has changing scaling properties generated by varying the local Hölder exponent. We show that multifractional Brownian motion is very sensitive to changes in the selected Hölder exponent and has extreme changes in magnitude. We suggest an alternative stochastic process, called integrated fractional white noise, which retains the important local properties but avoids the undesirable oscillations in magnitude. We also show how the Hölder exponent can be estimated locally from discrete data in this model.

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Auditory Selective Attention in Cerebral-Palsied Individuals

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.1604.260 ◽

1985 ◽

Vol 16 (4) ◽

pp. 260-266 ◽

Cited By ~ 4

Author(s):

Lee Ann Laraway

Keyword(s):

Selective Attention ◽

White Noise ◽

Normal Subjects ◽

Auditory Selective Attention ◽

Normal Individuals ◽

Significant Difference

The purpose of this study was to determine whether there is a statistically significant difference between the auditory selective attention abilities of normal and cerebral-palsied individuals. Twenty-three cerebral-palsied and 23 normal subjects between the ages of 5 and 21 were asked to repeat a series of 30 items consisting of from 2 to 4 digits in the presence of intermittent white noise. Results of the study indicate that cerebral-palsied individuals perform significantly poorer than normal individuals when the stimulus is accompanied by noise. Noise was not a significant factor in the performance of the normal subjects regardless of age.

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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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White Noise and Stuttering

Journal of Speech and Hearing Research ◽

10.1044/jshr.0401.72 ◽

1961 ◽

Vol 4 (1) ◽

pp. 72-72 ◽

Cited By ~ 24

Author(s):

Samuel Sutton ◽

Richard Allen Chase

Keyword(s):

White Noise

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Infant Responses to Recorded Sounds

Journal of Speech and Hearing Research ◽

10.1044/jshr.1104.811 ◽

1968 ◽

Vol 11 (4) ◽

pp. 811-816 ◽

Cited By ~ 7

Author(s):

Maurice I. Mendel

Keyword(s):

White Noise ◽

Narrow Band ◽

Limited Bandwidth ◽

Broadband Spectrum ◽

Continuous Band

Thirty infants, ranging in age from 4 to 11 months, were tested with five different recorded sounds that varied in bandwidth and temporal configuration: a continuous band of white noise, the same band of noise interrupted twice per second, the crinkling of onionskin paper, a narrow band of noise centered at 3000 Hz, and a warbled 3000 Hz tone. With loudness and duration of the stimuli held constant, more responses occurred to sounds composed of a broadband spectrum than to those of a limited bandwidth. Temporal configuration of the sound had no effect on the number of responses elicited.

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