Experimental Design for Estimating Area under the Curve by Trapezoidal Approximation in Destructive Sampling

1997 ◽  
Vol 31 (4) ◽  
pp. 1237-1242 ◽  
Author(s):  
Greg C. G. Wei
Keyword(s):  
Experimental Design ◽  
Area Under The Curve ◽  
Destructive Sampling

Identifying suboptimalities with factorial model comparison

2018 ◽  
Vol 41 ◽  
Author(s):  
Wei Ji Ma
Keyword(s):  
Experimental Design ◽  
Model Comparison ◽  
Process Models ◽  
Multiple Forms ◽  
Factorial Experimental Design ◽  
Factorial Model ◽  
Multiple Components ◽  
The Many

AbstractGiven the many types of suboptimality in perception, I ask how one should test for multiple forms of suboptimality at the same time – or, more generally, how one should compare process models that can differ in any or all of the multiple components. In analogy to factorial experimental design, I advocate for factorial model comparison.

Combining integrated systems-biology approaches with intervention-based experimental design provides a higher-resolution path forward for microbiome research

2019 ◽  
Vol 42 ◽  
Author(s):  
J. Alfredo Blakeley-Ruiz ◽  
Carlee S. McClintock ◽  
Ralph Lydic ◽  
Helen A. Baghdoyan ◽  
James J. Choo ◽  
...  
Keyword(s):  
Systems Biology ◽  
High Resolution ◽  
Experimental Design ◽  
Integrated Systems ◽  
Microbiome Research ◽  
Constructive Criticism

Abstract The Hooks et al. review of microbiota-gut-brain (MGB) literature provides a constructive criticism of the general approaches encompassing MGB research. This commentary extends their review by: (a) highlighting capabilities of advanced systems-biology “-omics” techniques for microbiome research and (b) recommending that combining these high-resolution techniques with intervention-based experimental design may be the path forward for future MGB research.

Statistics and parallaxes

1978 ◽  
Vol 48 ◽  
pp. 7-29
Author(s):  
T. E. Lutz
Keyword(s):  
Experimental Design ◽  
Statistical Methods ◽  
Review Paper ◽  
Systematic Errors ◽  
Past Experience ◽  
Random Errors ◽  
Trigonometric Parallaxes ◽  
Systematic And Random Errors

This review paper deals with the use of statistical methods to evaluate systematic and random errors associated with trigonometric parallaxes. First, systematic errors which arise when using trigonometric parallaxes to calibrate luminosity systems are discussed. Next, determination of the external errors of parallax measurement are reviewed. Observatory corrections are discussed. Schilt’s point, that as the causes of these systematic differences between observatories are not known the computed corrections can not be applied appropriately, is emphasized. However, modern parallax work is sufficiently accurate that it is necessary to determine observatory corrections if full use is to be made of the potential precision of the data. To this end, it is suggested that a prior experimental design is required. Past experience has shown that accidental overlap of observing programs will not suffice to determine observatory corrections which are meaningful.

Predictors of Purchasing a Hearing Aid After an Evaluation Period: A Prospective Study in Dutch Older Hearing Aid Candidates

2019 ◽  
Vol 28 (3S) ◽  
pp. 802-805 ◽  
Author(s):  
Marieke Pronk ◽  
Janine F. J. Meijerink ◽  
Sophia E. Kramer ◽  
Martijn W. Heymans ◽  
Jana Besser
Keyword(s):  
Help Seeking ◽  
Hearing Aid ◽  
Model Performance ◽  
Area Under The Curve ◽  
Secondary Data ◽  
Support Program ◽  
Evaluation Period ◽  
A Prospective Study ◽  
Study Participants ◽  
Baseline Covariates

Purpose The current study aimed to identify factors that distinguish between older (50+ years) hearing aid (HA) candidates who do and do not purchase HAs after having gone through an HA evaluation period (HAEP). Method Secondary data analysis of the SUpport PRogram trial was performed ( n = 267 older, 1st-time HA candidates). All SUpport PRogram participants started an HAEP shortly after study enrollment. Decision to purchase an HA by the end of the HAEP was the outcome of interest of the current study. Participants' baseline covariates (22 in total) were included as candidate predictors. Multivariable logistic regression modeling (backward selection and reclassification tables) was used. Results Of all candidate predictors, only pure-tone average (average of 1, 2, and 4 kHz) hearing loss emerged as a significant predictor (odds ratio = 1.03, 95% confidence interval [1.03, 1.17]). Model performance was weak (Nagelkerke R 2 = .04, area under the curve = 0.61). Conclusions These data suggest that, once HA candidates have decided to enter an HAEP, factors measured early in the help-seeking journey do not predict well who will and will not purchase an HA. Instead, factors that act during the HAEP may hold this predictive value. This should be examined.

Using Video Modeling Intervention and Speech Generating Devices To Teach Requesting Behaviors to Persons With Autism

2011 ◽  
Vol 20 (4) ◽  
pp. 109-113
Author(s):  
Karen Copple ◽  
Rajinder Koul ◽  
Devender Banda ◽  
Ellen Frye
Keyword(s):  
Developmental Disabilities ◽  
Experimental Design ◽  
Communication Skills ◽  
Observational Learning ◽  
Video Modeling ◽  
Single Subject ◽  
Design Studies ◽  
Communicative Behaviors ◽  
Speech Generating Device ◽  
Treatment Package

Abstract One of the instructional techniques reported in the literature to teach communication skills to persons with autism is video modeling (VM). VM is a form of observational learning that involves watching and imitating the desired target behavior(s) exhibited by the person on the videotape. VM has been used to teach a variety of social and communicative behaviors to persons with developmental disabilities such as autism. In this paper, we describe the VM technique and summarize the results of two single-subject experimental design studies that investigated the acquisition of spontaneous requesting skills using a speech generating device (SGD) by persons with autism following a VM intervention. The results of these two studies indicate that a VM treatment package that includes a SGD as one of its components can be effective in facilitating communication in individuals with autism who have little or no functional speech.

A randomized cross-over trial in patients suspected of PAD on diagnostic accuracy of ankle-brachial index by Doppler-based versus four-point oscillometry based measurements

VASA ◽  
2019 ◽  
Vol 48 (6) ◽  
pp. 516-522 ◽  
Author(s):  
Verena Mayr ◽  
Mirko Hirschl ◽  
Peter Klein-Weigel ◽  
Luka Girardi ◽  
Michael Kundi
Keyword(s):  
Diagnostic Accuracy ◽  
Ankle Brachial Index ◽  
Area Under The Curve ◽  
High Volume ◽  
Epidemiologic Studies ◽  
Lower Sensitivity ◽  
Oscillometric Device ◽  
Specificity And Sensitivity ◽  
Time Requirements ◽  
Peripheral Arterial

Summary. Background: For diagnosis of peripheral arterial occlusive disease (PAD), a Doppler-based ankle-brachial-index (dABI) is recommended as the first non-invasive measurement. Due to limitations of dABI, oscillometry might be used as an alternative. The aim of our study was to investigate whether a semi-automatic, four-point oscillometric device provides comparable diagnostic accuracy. Furthermore, time requirements and patient preferences were evaluated. Patients and methods: 286 patients were recruited for the study; 140 without and 146 with PAD. The Doppler-based (dABI) and oscillometric (oABI and pulse wave index – PWI) measurements were performed on the same day in a randomized cross-over design. Specificity and sensitivity against verified PAD diagnosis were computed and compared by McNemar tests. ROC analyses were performed and areas under the curve were compared by non-parametric methods. Results: oABI had significantly lower sensitivity (65.8%, 95% CI: 59.2%–71.9%) compared to dABI (87.3%, CI: 81.9–91.3%) but significantly higher specificity (79.7%, 74.7–83.9% vs. 67.0%, 61.3–72.2%). PWI had a comparable sensitivity to dABI. The combination of oABI and PWI had the highest sensitivity (88.8%, 85.7–91.4%). ROC analysis revealed that PWI had the largest area under the curve, but no significant differences between oABI and dABI were observed. Time requirement for oABI was significantly shorter by about 5 min and significantly more patients would prefer oABI for future testing. Conclusions: Semi-automatic oABI measurements using the AngER-device provide comparable diagnostic results to the conventional Doppler method while PWI performed best. The time saved by oscillometry could be important, especially in high volume centers and epidemiologic studies.

Nepotism in the Hiring of Leaders

2014 ◽  
Vol 73 (4) ◽  
pp. 243-248 ◽  
Author(s):  
Annick Darioly ◽  
Ronald E. Riggio
Keyword(s):  
Experimental Design ◽  
Perceived Competence ◽  
Negative Evaluation ◽  
Leadership Position ◽  
Family Ties ◽  
Hiring Decision ◽  
Job Application ◽  
Career Progress

This study examines how applicants who are relatives of the company’s executives are perceived when they are being considered for a leadership position. In a 2 (Family ties: with vs. without) × 2 (Applicant qualifications: well-qualified vs. underqualified) experimental design, 165 Swiss employees read the applicant’s job application and evaluated the hiring decision, the perceived competence, and the perceived career progress of the target employee. This research showed that even a well-qualified potential employee received a more negative evaluation if the candidate had family ties to the company. Despite their negative evaluation of potential nepotistic hires, the participants nevertheless believed that family ties would boost the career progress of an underqualified applicant. Limitations and implications are discussed.

A Pilot Study on the Efficacy of Volunteer Mentorship for Young Adults With Self-Harm Behaviors Using a Quasi-Experimental Design

Crisis ◽  
2016 ◽  
Vol 37 (6) ◽  
pp. 415-426 ◽  
Author(s):  
Yik-Wa Law ◽  
Paul S. F. Yip ◽  
Carmen C. S. Lai ◽  
Chi Leung Kwok ◽  
Paul W. C. Wong ◽  
...  
Keyword(s):  
Experimental Design ◽  
Suicide Ideation ◽  
Intervention Group ◽  
Well Being ◽  
Control Group ◽  
Treatment As Usual ◽  
Prevention Services ◽  
Quasi Experimental ◽  
Self Harm ◽  
Volunteer Support

Abstract. Background: Studies have shown that postdischarge care for self-harm patients is effective in reducing repeated suicidal behaviors. Little is known about whether volunteer support can help reduce self-harm repetition and improve psychosocial well-being. Aim: This study investigated the efficacy of volunteer support in preventing repetition of self-harm. Method: This study used a quasi-experimental design by assigning self-harm patients admitted to the emergency departments to an intervention group with volunteer support and treatment as usual (TAU) for 9 months and to a control group of TAU. Outcome measures include repetition of self-harm, suicidal ideation, hopelessness, and level of depressive and anxiety symptoms. Results: A total of 74 cases were recruited (38 participants; 36 controls). There were no significant differences in age, gender, and clinical condition between the two groups at the baseline. The intervention group showed significant improvements in hopelessness and depressive symptoms. However, the number of cases of suicide ideation and of repetition of self-harm episodes was similar for both groups at the postintervention period. Conclusion: Postdischarge care provided by volunteers showed significant improvement in hopelessness and depression. Volunteers have been commonly involved in suicide prevention services. Further research using rigorous methods is recommended for improving service quality in the long term.

The Cortisol Response to Normal and Nocturnal Awakening

2000 ◽  
Vol 14 (1) ◽  
pp. 24-28 ◽  
Author(s):  
F. Hucklebridge ◽  
A. Clow ◽  
H. Rahman ◽  
P. Evans
Keyword(s):  
Area Under The Curve ◽  
Secretory Activity ◽  
Linear Increase ◽  
Cortisol Response ◽  
The Awakening ◽  
Basal Cortisol ◽  
Free Cortisol ◽  
Main Effect ◽  
Nocturnal Awakening ◽  
Night Awakening

Abstract Free cortisol as measured in saliva increases markedly following awakening. It is not clear, however, whether this is truly a stress-neuroendocrine response to awakening or a manifestation of the hypothalamic-pituitary-adrenal (HPA) circadian cycle. We investigated whether the awakening cortisol response can be generated in the middle of nocturnal sleep, when secretory activity in the HPA axis is low. In a within subject design, salivary cortisol response was measured under three different awakening conditions: (1) awakening at the normal morning awakening time; (2) awakening four hours prior to normal awakening time, and (3) awakening the following morning after interrupted sleep. The overall main effect was a linear increase in free cortisol following awakening with no significant interaction with awakening condition. Cortisol levels, as determined by area under the cortisol curve calculated with reference to zero, did differ by awakening condition. The two morning awakening conditions were comparable but values were lower for night awakening. Area under the curve change (calculated with reference to the first awakening cortisol base value), however, did not distinguish the three awakening conditions. We conclude from these data that there is a clear free cortisol response to awakening for both nocturnal and morning awakening although the absolute levels produced are lower for nocturnal awakening when basal cortisol is low. Nocturnal interruption of sleep did not affect the subsequent morning response.

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