Item-fit evaluation in biased tests: a study under Rasch model

In this paper, the power rates and distributional properties of the Outfit, Infit, Lz, ECI2z and ECI4z statistics when they are used in tests with biased or differential item functioning (DIF) were explored. In this study, different conditions of sample size, sample size ratio focal and reference group, impact between groups, DIF effect size, and percentage of DIF items were manipulated. In addition, examinee responses were generated to simulate uniform DIF. Results suggest that item fit statistics generally detected medium percents of DIF in large samples (1000/500 or 1000/1000) only when DIF effect size was relatively high and when the mean of focal and reference group was different. Moreover, when groups had equal mean, low correct identification rates were found in the five item-fit indices. In general, the results showed adequate control of false positive rates. These findings lead to the conclusion that all indices used in this study are partially adequate fit measures for detecting biased items, mainly when impact between groups is present and sample size is large.     

Using Mokken scale analysis to develop unidimensional scales

This paper describes Mokken scale analysis as a method for assessing the unidimensionality of a set of items. As a nonparametric stochastic version of Guttman scale analysis, the Mokken model provides a useful starting point in scale construction since it does not impose severe restrictions on the functional form of the item trace lines. It requires only that the item trace lines are monotonically increasing and that they do not cross. After describing the Mokken method, we illustrate it by analyzing six abortion items from the 1975–1984 NORC General Social Surveys. In contrast to earlier parametric analyses of these items (regular and probit factor analyses), we find that these items form a single dimension. We argue that the two-dimension solution of these earlier analyses is an artifact of the differences in the difficulty of the items.     

清单计价模式下措施项目缺项引起的价款调整研究

本研究对措施项目缺项的价款调整问题进行了阐述,提出三大关键问题:影响措施项目缺项的因素分析、措施项目缺项的价款调整条件、措施项目缺项的价款调整分析。同时,本研究将导致措施项目缺项的原因进行责任与风险范围划分,对导致缺项的责任进一步分类后,给予相应的调整条件。通过对调整条件的分析,梳理出总价措施项目费与单价措施项目费的调整方法,对实际项目中措施项目费的价款调整提供了指导。     

A comparison of multiple imputation with EM algorithm and MCMC method for quality of life missing data

This study investigated the performance of multiple imputations with Expectation-Maximization (EM) algorithm and Monte Carlo Markov chain (MCMC) method in missing data imputation. We compared the accuracy of imputation based on some real data and set up two extreme scenarios and conducted both empirical and simulation studies to examine the effects of missing data rates and number of items used for imputation. In the empirical study, the scenario represented item of highest missing rate from a domain with fewest items. In the simulation study, we selected a domain with most items and the item imputed has lowest missing rate. In the empirical study, the results showed there was no significant difference between EM algorithm and MCMC method for item imputation, and number of items used for imputation has little impact, either. Compared with the actual observed values, the middle responses of 3 and 4 were over-imputed, and the extreme responses of 1, 2 and 5 were under-represented. The similar patterns occurred for domain imputation, and no significant difference between EM algorithm and MCMC method and number of items used for imputation has little impact. In the simulation study, we chose environmental domain to examine the effect of the following variables: EM algorithm and MCMC method, missing data rates, and number of items used for imputation. Again, there was no significant difference between EM algorithm and MCMC method. The accuracy rates did not significantly reduce with increase in the proportions of missing data. Number of items used for imputation has some contribution to accuracy of imputation, but not as much as expected.     

The applicability of the Tampa Scale of Kinesiophobia for patients with sub-acute neck pain: a qualitative study

The purpose of this study was to qualitatively evaluate patients understanding and interpretation of the wording used in test items of the Tampa Scale of Kinesiophobia (TSK). The TSK was developed to measure fear of movement in patients suffering from low back pain. The TSK is being increasingly used for other pain conditions. Patients with sub-acute neck pain experience problems while completing this questionnaire. The aim of this study was to elicit these problems. The study was conducted within the framework of a randomised controlled trial. The Three-Step Test Interview (TSTI) was used to collect data on the thoughts or considerations of respondents while completing the TSK. In the analysis, each transcribed interview was divided into three segments. The thoughts and considerations were then analysed and categorised per item. During the TSTI two problems were identified. One concerned the meaning of specific words used, like “dangerous” and “injury”. The other problem was that several implicit assumptions within some items make it difficult for respondents to answer these items. It was concluded that in the development and validation of questionnaires like the TSK, not only quantitative psychometric properties are important, but also qualitative research has an important contribution to enhance applicability.     

Comparison of four common data collection techniques to elicit preferences

We compare four common data collection techniques to elicit preferences: the rating of items, the ranking of items, the partitioning of a given amount of points among items, and a reduced form of the technique for comparing items in pairs. University students were randomly assigned a questionnaire employing one of the four techniques. All questionnaires incorporated the same collection of items. The data collected with the four techniques were converted into analogous preference matrices, and analyzed with the Bradley–Terry model. The techniques were evaluated with respect to the fit to the model, the precision and reliability of the item estimates, and the consistency among the produced item sequences. The rating, ranking and budget partitioning techniques performed similarly, whereas the reduced pair comparisons technique performed a little worse. The item sequence produced by the rating technique was very close to the sequence obtained averaging over the three other techniques.     

Identifying Optimal Items in Quality of Life Assessment

Quality of life has drawn increasing attention in health science and more efforts have been devoted to develop instruments that are valid and reliable to assess quality of life. The World Health Organization (WHO) has devised an instrument World Health Organization Quality of Life Survey- Abbreviated Version (WHOQOL-BREF) to assess quality of life, but the psychometric property of each individual item has not been studied yet. Using item response theory, we examine the properties of the WHOQOL-BRIEF Taiwan version. Samejima’s graded response model was fitted, and item parameters were calculated. The items were ranked base on their discrimination power, and the best items are identified. Several data with subset of items (22, 20, 18, 16 and 14 items) were created by omitting items with lower discrimination power. The test information function of the full questionnaire and the subsets were compared. The results showed there were significant positive correlations between the full questionnaire and the subsets of items and the distributions are similar. The test information function showed the maximum amount of test information spaced over two ends of the theta continuum, and this suggested that the WHOQOL-BREF provided more information for groups with either lower or higher satisfaction of quality of life, while it is less discriminating for individuals in the middle range.     

An alternative procedure for taking a random sample

Summary The procedure proposed consists in going through the population to be sampled item by item deciding each time with probability p whether the item at hand shall be incorporated in the sample. The "distances" between successive items in the sample will then form a random sample from a geometric distribution. A series of these random distances can easily be produced on a computer and can be conveniently used for taking the sample required. In some cases this method may have its advantages over the conventional use of a table of random numbers.     

CPI revision provides more accuracy in the medical care services component.

This revision, as in the past, enabled the Bureau to update medical care service expenditure weights in the CPI, including a more complete allocation of health insurance premiums. Instead of keeping the portion of premiums that go to benefits under health insurance, the expenditure weight for each benefit category has been added to the appropriate out-of-pocket expense. The unpublished health insurance item represents only the retained earnings portion of premiums paid by households. The specific item categories included in medical care services have also been updated and expanded. A study conducted during the developmental phase of the revision indicated that the Bureau should expand the eligible priced rates for physicians in the CPI to include not only the "self-pay" rate, but also other categories of payment as well. Another study indicated that the direct pricing of health insurance is not feasible because of the difficulty of factoring out from premium changes the effect of utilization levels and modified coverage. In pricing medical care service items, as with other item categories in the CPI, BLS attempts to exclude from price movement the effect of quality changes. However, some quality changes are difficult to assess or are not readily identified, for example, a change in the ratio of nurses to patients, and such changes may be reflected as part of the price change movement in the CPI.     

On the retention of finished goods inventory when reorder-occurrence is uncertain

Finished goods inventory may accumulate for a variety of reasons in the production of lowdemand or slow-moving items. In this article a simple model is developed and some results are presented to aid in making inventory retention decisions when there exists uncertainty about whether reorders for a slow-moving item will be received in the future. In formulating the model, it is assumed that some excess inventory remains after filling a customer order and that a single reorder for the item is possible. The problem is to determine how long to retain the inventory before disposing of it.The relevant expected costs of retaining some quantity of inventory for a period of time consist of two types: (1) the inventory carrying cost less the salvage value from disposal; and (2) the future production cost incurred due to premature disposal. Using conventional optimization, a relationship for finding the optimal retention period is derived and conditions are identified that ensure that the optimal retention period can be obtained directly from the relationship.To determine the optimal retention period, probability distributions are required for the interarrival time until the reorder occurs and for the reorder quantity. While it seems logical to assume that each item would have its own distributions, this argument leads to a specification problem since the data needed to establish distributions for individual items will generally not be available for slow-moving items. One approach used to overcome this problem in practice is to combine data for a selected group of items and use the combined data to obtain distributions useful for any or all of the items in the group. An example illustrating this approach is provided.     

How to examine construct validity of item banks

In this study data is brought to support an approach for assuring the content validity of item banks and for examining their construct validity. The method is an application of Guttman's concept of using mapping sentences for theory construction in the domain of “simple fraction’. The construct validity of the theory used for the creation of the item bank was tested by selecting two samples of items which are referenced in the same structuple (criterion). The Yule weak monotonicity coefficients of the items' connections were calculated and represented in two different matrices and in two different space diagrams. The results show clearly a similarity in both the structure of the space diagrams of any two parallel samples and in the partition of the points into regions, i.e., regions according to the classification of the items represented by them on the basis of the facets defined by the mapping sentences. Consequently, it may be concluded that the results support the construct validity of the theory on the basis of which the bank has been created.     

Increase in Precision when Estimating Parameters in Computer Assisted Testing Using Response Time

A model is given in this article that associates response time to each item with its relative difficulty for the person examined. The properties of the model are presented with respect to the quantity of information, while deducing the parameter estimators. Likewise, an empirical study to prove the feasibility and plausibility of the model is carried out, feasibility being understood as the existence of adequate estimators for the parameters of the model and plausibility the adjustment of the model proposed to the items in a spatial aptitude test used to demonstrate this (Rotation of solid figures). For this, the model is tested with simulated data, comparing the behaviour of the estimates carried out on the model proposed with the estimates made by a programme such as BILOG-MG. It is shown that, with the exception of parameter c (pseudo-chance) which does not benefit from the inclusion of the response time, the estimates for the model are always higher for parameters a (discrimination) and b (difficulty) of the items, always giving rise to a higher correlation with the original data, in spite of the inefficiency of the computation algorithm employed. The results suggest that the use of response time supplies as much information or more than the use of very informative a priori distributions.     

A performance matrix for strategies to improve satisfaction among faculty members in higher education

Most studies of higher education focus on students as ??customers??, and these studies tend to evaluate educational services on the basis of the satisfaction of these customers. This approach often neglects the question of the satisfaction (or dissatisfaction) of faculty members. The study designs a questionnaire for higher-education faculty members on the basis of the literature on this subject and discussion with scholars. Surveys of importance and satisfaction are then undertaken among Taiwanese faculty members with respect to various items. Each item is then placed on was modified a performance control matrix to determine an appropriate improvement strategy. Items that are found to be outside the range of an appropriate performance zone (APZ) are identified as objectives for improvement. The quality loss function (QLF) is then adopted to calculate an area of improvement objectives. A large QLF value indicates that faculty members satisfaction needs to be improved in these items. The results of this investigation demonstrate that retirement arrangements, job security, salaries, and fair promotion systems need to be improved. The resources of higher-education institutions must be invested appropriately to avoid waste and to enhance satisfaction among faculty members.     

ACTIVITIES OF MIDDLE MANAGERS — A TRAINING GUIDE

Abstract T his article argues that the teaching of practical management skills could, with advantage, be given more prominence in post-graduate and post-experience courses. If transference of learning is to take place, then the context in which the skills are practised on the job has to be discovered. Six items, selected from a previous research study of what managers do, were given to students enrolled for management courses. The results suggest that trouble shooting, forward planning, and briefing subordinates are important aspects of many managers'jobs. Teachers could ask their own students these questions, (or others of a similar nature) and formulate their practical skills objectives in response to the answers received. Suggestions on how this might be done are provided. If followed, the customer appeal of courses would be considerably enhanced.     

Nonuniform DIF Detection using Discriminant Logistic Analysis and Multinomial Logistic Regression: A comparison for polytomous items

This study focused on the effectiveness in nonuniform polytomous item DIF detection using Discriminant Logistic Analysis (DLA) and Multinomial Logistic Regression (MLR). A computer simulation study was conducted to compare the effect of using DLA and MLR, applying either an iterative test purification procedure or non-iterative to detect nonuniform DIF. The conditions under study were: DIF effect size (0.5, 1.0 and 1.5), sample size (500 and 1000), percentage of DIF items in the test (0, 10 and 20%) and DIF type (nonuniform). The results suggest that DLA is more accurate than MLR in detecting DIF. However, the purification process only improved the correct detection rate when MLR was applied. The false positive rates for both procedures were similar. Moreover, when the test purification procedure was used, the proportion of non-DIF items that were detected as DIF decreased for both procedures, although the false positive rates were smaller for DLA than for MLR.     

Augmenting the use of the Rasch model under time constraints

This paper proposes a method for estimating national standardizations of partially speeded tests composed of items from a previously standardized item bank. The model combines two submodels, one for whether the examinee reaches the item, and the second for whether she is successful if she does reach it. The former model is comparable to that for survival analysis using item position in test as a quasi-time parameter (Hutchison 1988). The latter is a straightforward Rasch Model. Combining the two submodels allows for the possibility that ability and drop-out were correlated. The model proposed here is superior that of Bolt et al. (2002), which divides the population into a speeded and a non-speeded group, in that it allows for a range of speededness effects. The model is tested using three UK national standardizations on one outcome and comparing the actual and predicted distributions. It is suggested that the observed discrepancies may be due to differences in the samples drawn, and that in some circumstances the model may actually produce a better estimate than an actual standardization exercise.     

In search of content validity: facet analysis as a qualitative method to improve questionnaire design

In this paper, two scales are examined for the measurement of self-regulation. The item content is evaluated for its specific usefulness for measuring self-regulation of obesity patients. Qualitative facet analysis (QFA), an application of Guttmann’s Facet Theory, is used to investigate whether item content sufficiently covers the intended content area. This form of content analysis constitutes a systematic, effective and critical tool for improving the content validity of questionnaires. It discovers topics that are underrepresented or overrepresented. The method offers a way to clarify the relationship between concrete item phrases and the desired content as defined by construct and theory. It allows the researcher to improve his or her understanding of the items as a stimulus and of the similarities of items, and allows the formulation of a possible structure for confirmative factor analysis. Various ways to improve the content of both scales are identified.     

The construction and initial validation of a measure of expatriate job performance

Based on Campbell's (1990, Handbook of Industrial and Organizational Psychology, 2nd ed., Palo Alto, CA: Consulting Psychologists Press, 687–732) multi-factorial model of job performance, the Expatriate Performance Scales were developed to measure components of expatriate performance. Item generation for the scales was informed by job performance theory, content analysis of interviews with expatriates and item sorting by subject matter experts. The scales (48 items) were administered to 106 Australian expatriates in the Special Administrative Regions of China. Data were subjected to exploratory factor analysis, reliability analysis as well as tests for criterion, convergent and discriminant validity. These procedures resulted in 32 items measuring an amended model of expatriate performance with six components: task performance, communication performance, demonstrating effort, maintaining personal discipline, team and leadership performance and management and administration performance. Results provide initial psychometric evidence of criterion, convergent and discriminant validity.     

CONFIDENCE INTERVALS FOR TEST INFORMATION AND RELATIVE EFFICIENCY

In latent theory the measurement properties of a mental test can be expressed in the test information function. The relative merits of two tests for the same latent trait can be described by the relative efficiency function, i.e. the ratio of the test information functions. It is argued that these functions have to be estimated if the values of the item difficulties are unknown. Using conditional maximum likelihood estimation as indicated by Andersen (1973), pointwise asymptotic distributions of the test information and relative efficiency function are derived for the case of dichotomously scored Rasch homogeneous items. Formulas for confidence intervals are derived from the asymptotic distributions. An application to a mathematics test is given and extensions to other latent trait models are discussed.     

“ASP动态网页设计技术”项目教学法的研究与实践

项目教学法是师生通过共同实施一个完整的项目而进行的教学活动,整个教学过程中既体现教师的主导作用又发挥学生的主观能动性,充分展示现代高职教育"以实践动手能力为奉"的教学目的。本文对项目教学法与传统的教学法相比较,介绍了项目教学法,并结合实践教学,以项目为中心对ASP动态网页设计技术课程教学进行了详细的教学设计。以整体的项目为例,通过确定项目任务、项目实施方案和项目验收及综合评价过程,阐述项目教学法在ASP动态网页设计技术课程设计中的具体应用。