Analytical Problems and Suggestions in the Analysis of Behavioral Economic Demand Curves

Behavioral economic demand curves (Hursh, Raslear, Shurtleff, Bauman, & Simmons, 1988) are innovative approaches to characterize the relationships between consumption of a substance and its price. In this article, we investigate common analytical issues in the use of behavioral economic demand curves, which can cause inconsistent interpretations of demand curves, and then we provide methodological suggestions to address those analytical issues.

We first demonstrate that log transformation with different added values for handling zeros changes model parameter estimates dramatically. Second, demand curves are often analyzed using an overparameterized model that results in an inefficient use of the available data and a lack of assessment of the variability among individuals.

To address these issues, we apply a nonlinear mixed effects model based on multivariate error structures that has not been used previously to analyze behavioral economic demand curves in the literature. We also propose analytical formulas for the relevant standard errors of derived values such as P _max, O _max, and elasticity. The proposed model stabilizes the derived values regardless of using different added increments and provides substantially smaller standard errors. We illustrate the data analysis procedure using data from a relative reinforcement efficacy study of simulated marijuana purchasing.     

Discovery and a Preliminary Study of the Parallel Lines Illusion Change Effect

The parallel lines illusion change effect (discovered by the authors) was studied: When the plane of a parallel-lines illusion figure intersects obliquely with the line of vision and the figure is rotated, using an imaginary perpendicular line between the parallel lines as the axis, the smaller the intersecting angle, the more the illusory effect decreases, until it disappears. If the illusion figure is rotated and any one of the parallel lines is used as the axis, then the smaller the intersecting angle, the greater the illusory effect. The parallel lines illusion change effect may be applicable to the study of geometric-figure illusions.     

An Introduction to Normalization and Calibration Methods in Functional MRI

In functional magnetic resonance imaging (fMRI), the blood oxygenation level dependent (BOLD) signal is often interpreted as a measure of neural activity. However, because the BOLD signal reflects the complex interplay of neural, vascular, and metabolic processes, such an interpretation is not always valid. There is growing evidence that changes in the baseline neurovascular state can result in significant modulations of the BOLD signal that are independent of changes in neural activity. This paper introduces some of the normalization and calibration methods that have been proposed for making the BOLD signal a more accurate reflection of underlying brain activity for human fMRI studies.     

Mother–infant interaction improves with a developmental intervention for mother–preterm infant dyads

While premature infants have a high need for positive interactions, both infants and their mothers are challenged by the infant‘s biological immaturity. This randomized clinical trial of 198 premature infants born at 29–34 weeks gestation and their mothers examined the impact of the H-HOPE (Hospital to Home: Optimizing the Infant's Environment) intervention on mother–premature infant interaction patterns at 6-weeks corrected age (CA). Mothers had at least 2 social environmental risk factors such as minority status or less than high school education. Mother–infant dyads were randomly assigned to the H-HOPE intervention group or an attention control group. H-HOPE is an integrated intervention that included (1) twice-daily infant stimulation using the ATVV (auditory, tactile, visual, and vestibular-rocking stimulation) and (2) four maternal participatory guidance sessions plus two telephone calls by a nurse-community advocate team. Mother–infant interaction was assessed at 6-weeks CA using the Nursing Child Assessment Satellite Training–Feeding Scale (NCAST, 76 items) and the Dyadic Mutuality Code (DMC, 6-item contingency scale during a 5-min play session). NCAST and DMC scores for the Control and H-HOPE groups were compared using t-tests, chi-square tests and multivariable analysis. Compared with the Control group (n = 76), the H-HOPE group (n = 66) had higher overall NCAST scores and higher maternal Social-Emotional Growth Fostering Subscale scores. The H-HOPE group also had significantly higher scores for the overall infant subscale and the Infant Clarity of Cues Subscale (p < 0.05). H-HOPE dyads were also more likely to have high responsiveness during play as measured by the DMC (67.6% versus 58.1% of controls). After adjustment for significant maternal and infant characteristics, H-HOPE dyads had marginally higher scores during feeding on overall mother–infant interaction (β = 2.03, p = 0.06) and significantly higher scores on the infant subscale (β = 0.75, p = 0.05) when compared to controls. In the adjusted analysis, H-HOPE dyads had increased odds of high versus low mutual responsiveness during play (OR = 2.37, 95% CI = 0.97, 5.80). Intervening with both mother and infant is a promising approach to help premature infants achieve the social interaction patterns essential for optimal development.     

Students’ Academic Cheating in Chinese Universities: Prevalence, Influencing Factors, and Proposed Action

Quantitative research about academic cheating among Chinese college students is minimal. This paper discusses a large survey conducted in Chinese colleges and universities which examined the prevalence of different kinds of student cheating and explored factors that influence cheating behavior. A structural equation model was used to analyze the data. Results indicate that organizational deterrence and individual performance have a negative impact on cheating while individual perceived pressure, peers’ cheating, and extracurricular activities have a positive impact. Recommendations are proposed to reduce the level of academic cheating in China. Many of these are universal in nature and applicable outside of China as well.     

加工时间和加工速度对工作记忆广度的影响

对工作记忆广度机制的四个模型:资源共享模型、任务转换假说、干扰说和时间资源共享模型进行了检验。以60名大学本科生为被试,完成工作记忆广度任务和转换任务。结果表明:加工时间和加工项目数不是影响工作记忆广度的主要因素;工作记忆广度受到加工速度的影响;工作记忆广度和线索-任务转换代价呈显著的负相关关系。结果支持时间资源共享模型,工作记忆广度取决于注意在加工和存储之间快速、灵活的转换。     

视觉和听觉通道下减法与乘法心算加工的ERP特征

研究加工通道的差异以及减法和乘法心算的编码特征,选择100道心算算式,在视觉和听觉两种输入通道下记录并分析了14例正常人的脑事件相关电位(ERP)。结果发现,视觉和听觉通道引发了趋势相反的早中期成分,在额区和中央区产生了显著分离。在慢波阶段,听觉通道下更多激活了颞区,而视觉通道下更多激活了顶-枕区,且慢电位的ERP特征也表现出通道差异。减法和乘法运算以左半球激活为主,但听觉通道下的顶区和颞区出现了显著的右半球优势。减法在视觉通道下优势较大,说明其主要依赖视空间表征;而乘法在听觉通道下更具优势,则主要是由于其以听觉的言语表征方式为主。     

The effects of task instructor status on prospective memory performance in preschoolers

The present study applied a 2 × 2 experimental design to assess prospective memory (PM) development across preschool age and to examine the effect of task instructor status (researcher vs. significant other) on PM performance in 80 preschool children. Participants were required to name pictures (ongoing task [OT]), and to remember to refrain from naming but instead give a different response to certain target cues (PM task). Although the OT was of comparable difficulty for both age groups (as indicated by no performance differences), results still indicated significantly higher PM performance in 5-year-olds than in 3-year-olds, confirming the age-related increase of PM capacities between 3 and 5 years. Furthermore, results showed a performance-enhancing effect of significant others as task instructors on both age-groups. Post-hoc analysis revealed that 3-year-olds instructed by a significant other still performed marginally worse than 5-year-olds instructed by a researcher, underlining the finding that substantial changes of PM capacities take place during early childhood.     

Formation of yittrium oxide in cemented carbides

Rare-earth (RE) elements are helpful in improving the mechanical properties of cemented carbides. In this work, the formation of Y₂O₃ in functionally graded cemented carbides is investigated using transmission electron microscopy. The results indicate that Y₂O₃ can stabilize the Co phase with the face-centred cubic structure (α-Co), since it has a cubic structure similar to the high-temperature Co phase. The α-Co phase has a higher plasticity than ε-Co, and this suggests a possible mechanism for the role of RE elements in toughening cemented carbides.     

Proactive Personality and Innovative Work Behavior: the Mediating Effects of Affective States and Creative Self-Efficacy in Teachers

The purpose of the current study was to examine the influence proactive personality on innovative work behavior in teaching profession and investigate the potential mediating effects of affective states and creative self-efficacy on this relationship. Proactive Personality Scale, Positive and Negative Affect Schedule, Creative self-efficacy Scale and Teachers’ Innovative Work Behavior Scale were administered to 352 primary and middle school teachers in China. Results showed that proactive personality was significantly positively associated with teachers’ innovative work behavior. Furthermore, mediation analyses revealed that the impact of proactive personality on teachers’ innovative work behavior were simply mediated by positive affect and creative self-efficacy and sequential mediated by positive affect–creative self-efficacy and negative affect–creative self-efficacy. These findings provide a new perspective in understanding the intervening mechanisms underlying proactive personality on innovative work behavior. The possible explanations and limitations are discussed.