Modeling Unobserved Consideration Sets for Household Panel Data

We propose a new method to model consumers' consideration and choice processes. We develop a parsimonious probit type model for consideration and a multinomial probit model for choice, given consideration. Unlike earlier models of consideration ours is not prone to the curse of dimensionality, while we allow for very general structures of unobserved dependence in consideration among brands. In addition, our model allows for state dependence and marketing mix effects on consideration. Unique to this study is that we attempt to establish the validity of existing practice to infer consideration sets from observed choices in panel data. To this end, we use data collected in an on-line choice experiment involving interactive supermarket shelves and post-choice questionnaires to measure the choice protocol and stated consideration levels. We show with these experimental data that underlying consideration sets can be successfully retrieved from choice data alone and that there is substantial convergent validity of the stated and inferred consideration sets. We further find that consideration is a function of point-of-purchase marketing actions such as display and shelf space, and of consumer memory for recent choices. Next, we estimate the model on IRI panel data. We have three main results. First, compared with the single-stage probit model, promotion effects are larger and are inferred with smaller variances when they are included in the consideration stage of the two-stage model. Promotion effects are significant only in the two-stage model that includes consideration, whereas they are not in a single-stage choice model. Second, the price response curves of

Item response theory evaluation of the biomedical scale of the Pain Attitudes and Beliefs Scale.

OBJECTIVES: The assessment of health care professionals' attitudes and beliefs towards musculoskeletal pain is essential because they are key determinants of their clinical practice behaviour. The Pain Attitudes and Beliefs Scale (PABS) biomedical scale evaluates the degree of health professionals' biomedical orientation towards musculoskeletal pain and was never assessed using item response theory (IRT). This study aimed at assessing the psychometric performance of the 10-item biomedical scale of the PABS scale using IRT. METHODS: Two cross-sectional samples (BeBack, n = 1016; DABS; n = 958) of health care professionals working in the UK were analysed. Mokken scale analysis (nonparametric IRT) and common factor analysis were used to assess dimensionality of the instrument. Parametric IRT was used to assess model fit, item parameters, and local reliability (measurement precision). RESULTS: Results were largely similar in the two samples and the scale was found to be unidimensional. The graded response model showed adequate fit, covering a broad range of the measured construct in terms of item difficulty. Item 3 showed some misfit but only in the DABS sample. Some items (i.e. 7, 8 and 9) displayed remarkably higher discrimination parameters than others (4, 5 and 10). The scale showed satisfactory measurement precision (reliability > 0.70) between theta values -2 and +3. DISCUSSION: The 10-item biomedical scale of the PABS displayed adequate psychometric performance in two large samples of health care professionals, and it is suggested to assess group-level professionals degree of biomedical orientation towards musculoskeletal pain

Boundary Limitation of Wavenumbers in Taylor-Vortex Flow

We report experimental results for a boundary-mediated wavenumber-adjustment mechanism and for a boundary-limited wavenumber-band of Taylor-vortex flow (TVF). The system consists of fluid contained between two concentric cylinders with the inner one rotating at an angular frequency $\Omega$. As observed previously, the Eckhaus instability (a bulk instability) is observed and limits the stable wavenumber band when the system is terminated axially by two rigid, non-rotating plates. The band width is then of order $\epsilon^{1/2}$ at small $\epsilon$ ($\epsilon \equiv \Omega/\Omega_c - 1$) and agrees well with calculations based on the equations of motion over a wide $\epsilon$-range. When the cylinder axis is vertical and the upper liquid surface is free (i.e. an air-liquid interface), vortices can be generated or expelled at the free surface because there the phase of the structure is only weakly pinned. The band of wavenumbers over which Taylor-vortex flow exists is then more narrow than the stable band limited by the Eckhaus instability. At small $\epsilon$ the boundary-mediated band-width is linear in $\epsilon$. These results are qualitatively consistent with theoretical predictions, but to our knowledge a quantitative calculation for TVF with a free surface does not exist.Comment: 8 pages incl. 9 eps figures bitmap version of Fig

The importance of harmonising diagnostic criteria sets for pathological grief

Five diagnostic criteria sets for pathological grief are currently used in research. Studies evaluating their performance indicate that it is not justified to generalise findings regarding prevalence rates and predictive validity across studies using different diagnostic criteria of pathological grief. We provide recommendations to move the bereavement field forward

Individual Sanctions for Competition Law Infringements: Pros, Cons and Challenges

Following the substantive harmonization in Regulation (EC) no. 1/2003, the European Commission has started more recently to focus on the harmonization of procedure and sanctions, and in January 2016, the European Parliament called for penalties against natural persons. This special issue looks at the current state of individual sanctions on the EU Member State level, examines from a comparative perspective the institutional challenges which these individual sanctions present, especially for leniency programmes, and discusses the pros and cons of introducing further individual, in particular criminal sanctions in Europe. It examines the experience with criminal sanctions in France, Germany, the United Kingdom and the United States, and presents empirical evidence on public attitudes towards competition law infringements in various Member States and the United States

Psychometric Properties of the Externalizing Spectrum Inventory:Replication and Extension across Clinical and Non-Clinical Samples

The Externalizing Spectrum Inventory aims at assessing personality features that underlie externalizing disorders such as substance abuse and antisocial behaviors. The objective was to replicate the psychometric properties of the 160-item Externalizing Spectrum Inventory in Dutch clinical and non-clinical samples. First, Cronbach's alpha, test-retest reliability and the factor structure were analyzed on a mixed sample of inpatients (n = 149), undergraduates (n = 227), and community participants (n = 178). The factor structure was evaluated through confirmatory and exploratory factor analyses; for the latter Parallel Analysis was used, based on Minimum Rank Factor Analysis. Next, the criterion validity was analyzed using the Aggression Questionnaire and the NEO-Five Factor Inventory as external measures. The Dutch Externalizing Spectrum Inventory subscales showed sufficient reliability (α=.68-.94; ICC=.68-.91), except in the undergraduate sample (α=.49-.96; ICC=.43-.97). The factor structure of the Externalizing Spectrum Inventory was not confirmed and the exploratory analysis yielded different factor solutions across samples. The criterion validity was supported with regard to trait aggression and partly supported with regard to the Five Factor Model. The results suggest that the ESI-160 and its original factor model can be used for prediction purposes. However, further research of the factor structure is strongly recommended

Does Speaking Two Dialects in Daily Life Affect Executive Functions? An Event-Related Potential Study

Whether using two languages enhances executive functions is a matter of debate. Here, we take a novel perspective to examine the bilingual advantage hypothesis by comparing bidialect with mono-dialect speakers’ performance on a non-linguistic task that requires executive control. Two groups of native Chinese speakers, one speaking only the standard Chinese Mandarin and the other also speaking the Southern-Min dialect, which differs from the standard Chinese Mandarin primarily in phonology, performed a classic Flanker task. Behavioural results showed no difference between the two groups, but event-related potentials recorded simultaneously revealed a number of differences, including an earlier P2 effect in the bi-dialect as compared to the mono-dialect group, suggesting that the two groups engage different underlying neural processes. Despite differences in the early ERP component, no between-group differences in the magnitude of the Flanker effects, which is an index of conflict resolution, were observed in the N2 component. Therefore, these findings suggest that speaking two dialects of one language does not enhance executive functions. Implications of the current findings for the bilingual advantage hypothesis are discussed