• 한국수학교육학회지시리즈B:순수및응용수학
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• 제20권1호
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• pp.59-70
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• 2013

The purpose of this study was to develop a zero-inflated Rasch (ZI-Rasch) model, a combination of the Rasch model and the ZIP model. The ZI-Rasch model was considered in this study as an appropriate alternative to the Rasch model for zero-inflated data. To investigate the relative appropriateness of the ZI-Rasch model, several analyses were conducted using PROC NLMIXED procedures in SAS under various simulation conditions. Sets of criteria for model evaluations (-2LL, AIC, AICC, and BIC) and parameter estimations (RMSE, and $r$) from the ZI-Rasch model were compared with those from the Rasch model. In the data-model fit indices, regardless of the simulation conditions, the ZI-Rasch model produced better fit statistics than did the Rasch model, even when the response data were generated from the Rasch model. In terms of item parameter ${\lambda}$ estimations, the ZI-Rasch model produced estimates similar to those of the Rasch model.

• 한국전문물리치료학회지
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• 제21권2호
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• pp.74-81
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• 2014

The versions of the Oswestry disability questionnaire (ODQ) is regarded as one of the most extensively used condition-specific instruments measuring disability resulting from low back pain. It has been shown to have adequate psychometrics, reliability, validity, and responsiveness as a whole, yet the summated total score of the instrument often provide little information to rehabilitation clinicians. A keyform analysis based on Rasch measurement model is an innovative way of illustrating the specific test items that an individual may or may not perform. By applying the keyform of the Rasch measurement model to the ODQ, rehabilitation clinicians may able to select more challenging ODQ items matching an individual's ability and document them as attainable treatment goals. The results demonstrated how a keyform analysis assist to setting possible goals for the treatment of individuals with low back pain. Forty-two individuals with low back pain were recruited from rehabilitation clinics in Gainesville, Florida. A series of Rasch analyses on the 10 items of the ODQ were performed using Winsteps software. The performance of two individuals on those 10 items was illustrated on the keyform. The keyform analysis of the Rasch measurement model may be translated into a useful tool for making clinical judgements.

• 한국전문물리치료학회지
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• 제20권3호
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• pp.89-99
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• 2013

The purposes of this study were: 1) to show the item difficulty hierarchy of walking/moving construct of the International Classification of Functioning, Disability and Health-Activity Measure (ICF-AM), 2) to evaluate the item-level psychometrics for model fit, 3) to describe the relevant physical activity defined by level of activity intensity expressed as Metabolic Equivalent of Tasks (MET), and 4) to explore what extent the empirical activity hierarchy of the ICF-AM is linked to the conceptual model based on the level of energy expenditure described as MET. One hundred and eight participants with lower extremity impairments were examined for the present study. A newly created activity measure, the ICF-AM using an item response theory (IRT) model and computer adaptive testing (CAT) method, has a construct on walking/moving construct. Based on the ICF category of walking and moving, the instrument comprised items corresponding to: walking short distances, walking long distances, walking on different surfaces, walking around objects, climbing, and running. The item difficulty hierarchy was created using Winstep software for 20 items. The Rasch analyses (1-parameter IRT model) were performed on participants with lower extremity injuries who completed the paper and pencil version of walking/moving construct of the ICF-AM. The classification of physical activity can also be performed by the use of METs that is often preferred to determine the level of physical activity. The empirical item hierarchy of walking, climbing, running activities of the ICF-AM instrument was similar to the conceptual activity hierarchy based on the METs. The empirically derived item difficulty hierarchy of the ICF-AM may be useful in developing MET-based activity measure questionnaires. In addition to convenience of applying items to questionnaires, implications of the finding could lead to the use of CAT method without sacrificing the objectivity of physiologic measures.

• 한국전문물리치료학회지
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• 제21권4호
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• pp.40-48
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• 2014

Differential item functioning (DIF) based on Rasch model can be used to examine whether the items function similarly across different groups and identify items that appear to be too easy or difficult after controlling for the ability levels of the compared groups. The Oswestry low back pain disability (Oswestry) has traditionally been proved as an effective instrument measuring disability resulting from low back pain (LBP). In this study, DIF method was used to explore whether items on the Oswestry perform similarly across two different groups (participants with LBP and no LBP). A series of Rasch analyses on the 10 items of the Oswestry were performed using Winsteps$^{(R)}$ software. Forty-two participants with back pain were recruited from 3 rehabilitation hospitals in Gainesville, Florida. Another 42 participants with no LBP were recruited from several public places in the rehabilitation hospitals. Based on the DIF analysis across the two groups, several items were found to have an uniform DIF. Participants with no LBP had more difficulty on lifting and personal care items and participants with LBP had more difficulty on sleeping and social life items. For non-LBP group, a high ceiling effects (83% of participants with non-LBP) was detected, which was not be able to be effectively measured with the Oswestry items. Although 4 items of the Oswestry function differently across the two groups, all items of the Oswestry were well targeted the LBP group.

• Research in Vestibular Science
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• 제17권4호
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• pp.152-159
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• 2018

Objectives: The Korean Dizziness Handicap Inventory (KDHI), which includes 25 patient-reported items, has been used to assess self-reported dizziness in Korean patients with Parkinson disease (PD). Nevertheless, few studies have examined the KDHI based on item-response theory within this population. The aim of our study was to address the feasibility and clinimetric properties of the KDHI instrument using polytomous Rasch measurement analysis. Methods: The unidimensionality, scale targeting, separation reliability, item difficulty (severity), and response category utility of the KDHI were statistically assessed based on the Andrich rating scale model. The utilities of the orderedresponse categories of the 3-point Likert scale were analyzed with reference to the probability curves of the response categories. The separation reliability of the KDHI was assessed based on person separation reliability (PSR), which is used to measure the capacity to discriminate among groups of patients with different levels of balance deficits. Results: Principal component analyses of residuals revealed that the KDHI had unidimensionality. The KHDI had satisfactory PSR and there were no disordered thresholds in the 3-point rating scale. However, the KDHI showed several issues for inappropriate scale targeting and misfit items (items 1 and 2) for Rasch model. Conclusions: The KDHI provide unidimensional measures of imbalance symptoms in patients with PD with adequate separation reliability. There was no statistical evidence of disorder in polytomous rating scales. The Rasch analysis results suggest that the KDHI is a reliable scale for measuring the imbalance symptoms in PD patients, and identified parts for possible amendments in order to further improve the linear metric scale.

• 한국전문물리치료학회지
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• 제20권4호
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• pp.22-31
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• 2013

The aim of the present study was to compare measurement precisions of the Oswestry Back Pain Disability Questionnaire (ODQ) and a computer adaptive testing (CAT) method. The ODQ has been regarded as one of the most reliable condition-specific measure for back pain for decades. Cross-sectional study was carried out with two independent convenient samples from two out-patient rehabilitation clinics for back pain ($n_1=42$) and non-back pain group ($n_2=42$). Participants were asked to fill out the ODQ and CAT of International Classification of Functioning, Disability and Health-Activity Measure (ICF-AM). A series of Rasch analyses were performed to calculate person ability measures. The CAT measures had greater relative precision in discriminating the groups than did the ODQ measure in comparisons of the relative precision. The CAT measure appears to be more effective than did the ODQ measure in terms of measurement precision. By administering test items calibrated in a way, CAT measures using item response theory may promise a means with measurement precision as well as efficiency.

• 영재교육연구
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• 제17권1호
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• pp.1-26
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• 2007

본 연구의 목적은 중학교 수학 영재를 수학 창의적 문제해결력 검사로 판별할 때, 유창성만을 기준으로 수학 창의적 문제해결력을 채점하는 방식의 신뢰도와 타당도를 검증하는데 있다. 이를 위해서 수학영역에서의 직관적 통찰능력, 정보의 조직화 능력, 추론능력, 일반화 및 적용능력, 추상화능력, 공간화/시각화 능력, 반성적 사고력을 요구하는 문항들로 구성된 검사를 개발했다. 고급한 수학적 사고력을 요구하며 정답이 하나인 폐쇄적인 수학문항 10개와 다양한 답이 가능한 개방적인 수학 문항 5개를 영재교육기관의 교육대상자 선발과정에 지원한 중학교 1학년 1,032명에게 실시했다. 교사들은 각 문제에 대해 타당한 답을 제시한 빈도로 유창성을 채점했다. 학생들의 반응을 Rasch의 1모수 문항반응모형을 기반으로 한 BIGSTEPS로 분석했다. 문항반응 분석결과, 유창성만으로 측정한 창의성을 기준으로 한 영재교육대상자 선발의 신뢰도, 타당도, 난이도, 변별도가 모두 양호한 것으로 나타났다. 특히 덜 정의되고, 덜 구조화되고, 신선한 문제일수록 영재교육대상자 선발과정에 지원한 학생들의 수학 창의적 문제해결력을 평가하는데 양호한 문제임이 확인되었다. 이 검사는 영재교육원 지원생들이 영재학급 지원생들보다 창의적 문제해결력에서 더 우수함을 확인해주었다. 이로써 유창성만을 기준으로 수학 창의적 문제해결력을 채점하는 방식이 효율적이며, 타당하고 신뢰로울 수 있음을 확인해 주었다.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제10권1호
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• pp.55-70
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• 2006

The purpose of this study was to develop math creative problem solving test in order to identify the mathematically gifted on the basis of their math creative problem solving ability and evaluate the goodness of the test in terms of its reliability and validity of measuring creativity in math problem solving on the basis of fluency in producing valid solutions. Ten open math problems were developed requiring math thinking abilities such as intuitive insight, organization of information, inductive and deductive reasoning, generalization and application, and reflective thinking. The 10 open math test items were administered to 2,029 Grade 5 students who were recommended by their teachers as candidates for gifted education programs. Fluency, the number of valid solutions, in each problem was scored by math teachers. Their responses were analyzed by BIGSTEPTS based on Rasch's 1-parameter item-response model. The item analyses revealed that the problems were good in reliability, validity, difficulty, and discrimination power even when creativity was scored with the single criteria of fluency. This also confirmed that the open problems which are less-defined, less-structured and non-entrenched were good in measuring math creativity of the candidates for math gifted education programs. In addition, it discriminated applicants for two different gifted educational institutions and between male and female students as well.

• 한국학교수학회논문집
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• 제9권3호
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• pp.405-424
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• 2006

본 연구는 수학 영재의 행동특성 검사 도구를 개발하는데 목적이 있다. 연구는 문헌 연구를 통해 수학 영재의 행동 특성을 추출하여 유목화한 후 측정변인으로 규정하였으며, 각각의 측정변인별로 문항을 개발하여 예비검사 과정을 통하여 최종적으로 51개 문항으로 구성된 검사 도구를 개발하였다. 기존에 영재교육을 받은 학생과 표준화된 수학 창의적 문제해결력에서 상의 10%와 교사 지명 학생 포함하여 424명을 연구 대상으로 본 검사를 실시하였다. 검사도구의 신뢰도와 타당도를 검증한 결과 높은 신뢰도(.95)를 확보하였으며 Rash 1모수 모형을 이용하여 내적 타당도를 검증하였다. 주성분 요인추출방법으로 요인을 추출하여 Varimax 방법으로 직각회전을 한 구인타당도 검증에서 일반적인 수학정신 능력 요인, 수학적 능력 요인, 정보 수집과 처리 능력 요인과 수학적 성향 요인이 추출되었다 따라서 본 연구에서 개발한 수학 영재 행동 특성 검사 도구는 신뢰도와 타당도가 양호하게 검증되었다고 볼 수 있다.