Not all nonnormal distributions are created equal: Improved theoretical and measurement precision.

This study evaluated the psychometric properties of a self-report scale for assessing perceived driver competence, labeled the Self-Efficacy Scale for Driver Competence (SSDC), using item response theory analyses. Two samples of Swedish driving-license examinees (n = 795; n = 714) completed two versions of the SSDC that were parallel in content. Prior work, using classical test theory analyses, has provided support for the validity and reliability of scores from the SSDC. This study investigated the measurement precision, item hierarchy, and differential functioning for males and females of the items in the SSDC as well as how the rating scale functions. The results confirmed the previous findings; that the SSDC demonstrates sound psychometric properties. In addition, the findings showed that measurement precision could be increased by adding items that tap higher self-efficacy levels. Moreover, the rating scale can be improved by reducing the number of categories or by providing each category with a label.

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Supplemental Material for Assessing Sluggish Cognitive Tempo and ADHD Inattention in Elementary Students: Empirical Differentiation, Invariance Across Sex and Grade, and Measurement Precision

Psychological Assessment ◽

10.1037/pas0000946.supp ◽

2020 ◽

Keyword(s):

Elementary Students ◽

Measurement Precision ◽

Sluggish Cognitive Tempo ◽

Cognitive Tempo

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Supplemental Material for Reconciling Information and Reliability in Scaling Local Measurement Precision: A Comment on O’Connor (2017)

Psychological Assessment ◽

10.1037/pas0000548.supp ◽

2018 ◽

Keyword(s):

Measurement Precision ◽

Local Measurement

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Null-Result Test for Effect on Weight from Large Electrostatic Charge

Physics ◽

10.3390/physics3020013 ◽

2021 ◽

Vol 3 (2) ◽

pp. 160-172

Author(s):

G. Hathaway ◽

L. L. Williams

Keyword(s):

Scalar Field ◽

Long Range ◽

Buoyancy Force ◽

Weak Field ◽

Electrostatic Charge ◽

Measurement Precision ◽

Test Results ◽

Static Test ◽

Null Result ◽

Test Objects

We report test results searching for an effect of electrostatic charge on weight. For conducting test objects of mass of order 1 kg, we found no effect on weight, for potentials ranging from 10 V to 200 kV, corresponding to charge states ranging from 10−9 to over 10−5 coulombs, and for both polarities, to within a measurement precision of 2 g. While such a result may not be unexpected, this is the first unipolar, high-voltage, meter-scale, static test for electro-gravitic effects reported in the literature. Our investigation was motivated by the search for possible coupling to a long-range scalar field that could surround the planet, yet go otherwise undetected. The large buoyancy force predicted within the classical Kaluza theory involving a long-range scalar field is falsified by our results, and this appears to be the first such experimental test of the classical Kaluza theory in the weak field regime, where it was otherwise thought identical with known physics. A parameterization is suggested to organize the variety of electro-gravitic experiment designs.

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Measurement Precision and Efficiency of Computerized Adaptive Testing for the Activities-specific Balance Confidence Scale in People With Stroke

Physical Therapy ◽

10.1093/ptj/pzab020 ◽

2021 ◽

Author(s):

Bryant A Seamon ◽

Steven A Kautz ◽

Craig A Velozo

Keyword(s):

Rasch Model ◽

Computerized Adaptive Testing ◽

Adaptive Testing ◽

Measurement Precision ◽

Strongly Correlated ◽

Computerized Adaptive Test ◽

Balance Confidence ◽

Adaptive Test ◽

The Rasch Model ◽

Confidence Scale

Abstract Objective Administrative burden often prevents clinical assessment of balance confidence in people with stroke. A computerized adaptive test (CAT) version of the Activities-specific Balance Confidence Scale (ABC CAT) can dramatically reduce this burden. The objective of this study was to test balance confidence measurement precision and efficiency in people with stroke with an ABC CAT. Methods We conducted a retrospective cross-sectional simulation study with data from 406 adults approximately 2-months post-stroke in the Locomotor-Experience Applied Post-Stroke (LEAPS) trial. Item parameters for CAT calibration were estimated with the Rasch model using a random sample of participants (n = 203). Computer simulation was used with response data from remaining 203 participants to evaluate the ABC CAT algorithm under varying stopping criteria. We compared estimated levels of balance confidence from each simulation to actual levels predicted from the Rasch model (Pearson correlations and mean standard error (SE)). Results Results from simulations with number of items as a stopping criterion strongly correlated with actual ABC scores (full item, r = 1, 12-item, r = 0.994; 8-item, r = 0.98; 4-item, r = 0.929). Mean SE increased with decreasing number of items administered (full item, SE = 0.31; 12-item, SE = 0.33; 8-item, SE = 0.38; 4-item, SE = 0.49). A precision-based stopping rule (mean SE = 0.5) also strongly correlated with actual ABC scores (r = .941) and optimized the relationship between number of items administrated with precision (mean number of items 4.37, range [4–9]). Conclusions An ABC CAT can determine accurate and precise measures of balance confidence in people with stroke with as few as 4 items. Individuals with lower balance confidence may require a greater number of items (up to 9) and attributed to the LEAPS trial excluding more functionally impaired persons. Impact Statement Computerized adaptive testing can drastically reduce the ABC’s test administration time while maintaining accuracy and precision. This should greatly enhance clinical utility, facilitating adoption of clinical practice guidelines in stroke rehabilitation. Lay Summary If you have had a stroke, your physical therapist will likely test your balance confidence. A computerized adaptive test version of the ABC scale can accurately identify balance with as few as 4 questions, which takes much less time.

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The Group Nurturance Inventory — initial psychometric evaluation using Rasch and factor analysis

BMC Public Health ◽

10.1186/s12889-021-11474-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Magnus Johansson ◽

Anthony Biglan

Keyword(s):

Factor Analysis ◽

Rasch Analysis ◽

Protective Factor ◽

Group Development ◽

Psychometric Evaluation ◽

Psychological Flexibility ◽

Well Being ◽

Measurement Precision ◽

Assessment Instrument ◽

Measurement Properties

Abstract Background This paper describes the development and psychometric evaluation of a behavioral assessment instrument primarily intended for use with workgroups in any type of organization. The instrument was developed based on the Nurturing Environments framework which describes four domains important for health, well-being, and productivity; minimizing toxic social interactions, teaching and reinforcing prosocial behaviors, limiting opportunities for problem behaviors, and promoting psychological flexibility. The instrument is freely available to use and adapt under a CC-BY license and intended as a tool that is easy for any group to use and interpret to identify key behaviors to improve their psychosocial work environment. Methods Questionnaire data of perceived frequency of behaviors relevant to nurturance were collected from nine different organizations in Sweden. Data were analyzed using confirmatory factor analysis, Rasch analysis, and correlations to investigate relationships with relevant workplace measures. Results The results indicate that the 23-item instrument is usefully divided in two factors, which can be described as risk and protective factors. Toxic social behaviors make up the risk factor, while the protective factor includes prosocial behavior, behaviors that limit problems, and psychological flexibility. Rasch analysis showed that the response categories work as intended for all items, item fit is satisfactory, and there was no significant differential item functioning across age or gender. Targeting indicates that measurement precision is skewed towards lower levels of both factors, while item thresholds are distributed over the range of participant abilities, particularly for the protective factor. A Rasch score table is available for ordinal to interval data transformation. Conclusions This initial analysis shows promising results, while more data is needed to investigate group-level measurement properties and validation against concrete longitudinal outcomes. We provide recommendations for how to work in practice with a group based on their assessment data, and how to optimize the measurement precision further. By using a two-dimensional assessment with ratings of both frequency and perceived importance of behaviors the instrument can help facilitate a participatory group development process. The Group Nurturance Inventory is freely available to use and adapt for both commercial and non-commercial use and could help promote transparent assessment practices in organizational and group development.

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Aerodynamic characteristics of a free-flight scramjet vehicle in shock tunnel

Experiments in Fluids ◽

10.1007/s00348-021-03229-0 ◽

2021 ◽

Vol 62 (7) ◽

Author(s):

Marie Tanno ◽

Hideyuki Tanno

Keyword(s):

System Analysis ◽

Force Measurement ◽

Prediction Interval ◽

Angular Acceleration ◽

Aerodynamic Characteristics ◽

Measurement Precision ◽

Shock Tunnel ◽

Free Flight ◽

Vehicle Model ◽

Aerodynamic Test

Abstract A multi-component aerodynamic test for an airframe-engine integrated scramjet vehicle model was conducted in the free-piston shock tunnel HIEST. A free-flight force measurement technique was applied to the scramjet vehicle model named MoDKI. A new method using multiple piezoelectric accelerometers was developed based on overdetermined system analysis. Its unique features are the following: (1) The accelerometer’s mounting location can be more flexible. (2) The measurement precision is predicted to be improved by increasing the number of accelerometers. (3) The angular acceleration can be obtained with single-axis translational accelerometers instead of gyroscopes. (4) Through the averaging process of the multiple accelerometers, model natural vibration is expected to be mitigated. With eight model-onboard single-axis accelerometers, the three-component aerodynamic coefficients (Drag, Lift, and Pitching moment) of MoDKI were successfully measured at the angle of attack from 0.7 to 3.4 degrees under a Mach 8 free-stream test flow condition. A linear regression fitting revealed a 95% prediction interval as the measurement precision of each aerodynamic coefficient. Graphical abstract

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