Effect of Asymmetric Anchoring Groups on Electronic Transport in Hybrid Metal/Molecule/Graphene Single Molecule Junctions.

A combined experimental and theoretical study on molecular junctions with asymmetry in both the electrode type and in the anchoring group type is presented. A scanning tunnelling microscope is used to create the "asymmetric" Au-S-(CH2 )n-COOH-graphene molecular junctions and determine their conductance. The measurements are combined with electron transport calculations based on density functional theory (DFT) to analyze the electrical conductance and its length attenuation factor from a series of junctions of different molecular length (n). These results show an unexpected trend with a rather high conductance and a smaller attenuation factor for the Au-S-(CH2 )n -COOH-graphene configuration compared to the equivalent junction with the "symmetrical" COOH contacting using the HOOC-(CH2 )n -COOH series. Owing to the effect of the graphene electrode, the attenuation factor is also smaller than the one obtained for Au/Au electrodes. These results are interpreted through the relative molecule/electrode couplings and molecular level alignments as determined with DFT calculations. In an asymmetric junction, the electrical current flows through the less resistive conductance channel, similarly to what is observed in the macroscopic regime

From Clinical Trial to Education: Methodologies, Assumptions, and Directions

In the field of education, emphasis on evidence-based practice, randomized controlled trials (RCTs), causal inference, and process evaluation can all find their roots back in clinical trials and medical research. This response paper surveys contemporary literature in psychometrics, process evaluation, and RCTs aiming to evaluate the feasibility and limitations of RCTs as a methodology in education and provide future directions. Based on the systematic literature review, the author argues: (1) A lack of significant positive treatment effect does not indicate that RCTs are not worth the investment. (2) A careful evaluation of the intervention itself, implementation process, and measurement instrument is recommended for RCTs. (3) There is the need to reframe some causal inference assumptions in an education setting. The paper also provides several examples of reframing assumptions and comments on the caveats. In conclusion, the author foresees a promising future for RCTs in education with the appropriate reframing of assumptions, process evaluation and replication, and recognition of the validity of parallel methodologies

From Clinical Trial to Education: Methodologies, Assumptions, and Directions

In the field of education, emphasis on evidence-based practice, randomized controlled trials (RCTs), causal inference, and process evaluation can all find their roots back in clinical trials and medical research. This response paper surveys contemporary literature in psychometrics, process evaluation, and RCTs aiming to evaluate the feasibility and limitations of RCTs as a methodology in education and provide future directions. Based on the systematic literature review, the author argues: (1) A lack of significant positive treatment effect does not indicate that RCTs are not worth the investment. (2) A careful evaluation of the intervention itself, implementation process, and measurement instrument is recommended for RCTs. (3) There is the need to reframe some causal inference assumptions in an education setting. The paper also provides several examples of reframing assumptions and comments on the caveats. In conclusion, the author foresees a promising future for RCTs in education with the appropriate reframing of assumptions, process evaluation and replication, and recognition of the validity of parallel methodologies

Effect of R&D investments on persistence of abnormal earnings

Purpose – This paper sets out to test the effects of firms’ and industry's R&D intensity on persistence of abnormal earnings. Design/methodology/approach – Ohlson's valuation model is used with pooled regressions along with Fama–Macbeth methodology on yearly regressions and partitioning on Herfindahl index to conduct the tests. Findings – It was found that firms’ and industries’ R&D intensities are both positively correlated with persistence of abnormal earnings. The evidence suggests that the positive effect on earnings persistence caused by R&D's effectiveness in mitigating competition dominates the negative effect brought by more risk from R&D projects Practical implications – The fact that the firm's own R&D investment leads to incremental earnings persistence beyond that of the industry suggests the importance of incorporating both industry and firm's R&D intensity in earnings persistence. While industry R&D investment leads to competition mitigation via creation of entry barriers, a firm's own investment in R&D differentiates its products from those of its competitors, and thereby results in further competition mitigation by creating replacement barriers. Originality/value – Finally, since R&D intensity is correlated with earnings persistence, inclusion of R&D intensity in future earnings persistence studies may lead to better model specification by reducing the problem of correlated omitted variables.Competitors, Project management, Research and development

Are PCAOB-Identified Audit Deficiencies Associated with a Change in Reporting Decisions of Triennially Inspected Audit Firms?

The primary issue we examine is whether PCAOB-identified audit deficiencies are associated with a change in triennially inspected audit firms\u27 going-concern (GC) reporting decisions for their financially distressed clients. Our analysis generally indicates that firms with PCAOB deficiencies were more likely to issue a GC opinion for financially distressed clients subsequent to their PCAOB inspection than prior to their inspection. We also examine the same issue for audit firms with a PCAOB inspection report indicating no audit deficiencies. For these firms, our results provide only limited evidence of a change in the likelihood of issuing a GC opinion, with audit firms becoming more conservative (i.e., greater likelihood of issuing a GC opinion)

Nonaudit services and earnings management in the Pre-SOX and Post-SOX eras

Concerns about the impact of auditor-provided nonaudit services (NAS) on auditor independence arise because of (1) auditors\u27 economic dependence on their clients, and (2) some specific types of NAS which the Securities and Exchange Commission (SEC) argues can harm auditor objectivity. The SEC\u27s prohibition in 2003 of specific kinds of NAS led to a significant decline in NAS between 2000-2001 and 2004- 2005. We argue that this decline in observed NAS fees can be used to identify firms that had a greater likelihood of impaired auditor independence in the pre-SOX period. Using discretionary accruals to proxy for earnings management, we find a positive association between discretionary accruals in the pre-SOX era and the subsequent reduction in NAS, but this was confined to income-decreasing accruals. Further, the association between downward earnings management and the decline in NAS was reduced in the post-SOX era