International Trade and Growth: The Impact of Seletion and Imitation

This paper develops an endogenous growth model with heterogeneous firms to analyze the impact of intra-industry trade on productivity growth. Growth is generated by selection, and sustained by entrants imitating successful incumbents. Firms are subject to idiosyncratic productivity shocks and some firms, mostly those with relatively low productivity levels, are forced to exit. This results in an increase in average productivity of the economy. The intraindustry effect of trade works through self-selection of the most productive firms into the export market. It leads to a reallocation of resources towards more efficient firms. Since the effect of selection and imitation on growth is amplified by the trade-induced selection process, opening up to trade increases the growth rate of productivity.Endogenous growth, Intra-industry trade, Heterogeneous firms, Selection

A Transferable Process Model for E-commerce in SMEs

Purpose: The overall objective to this study was the creation of a transferable strategic process model, designed to aid the implementation of e-commerce within UK SMEs. The proposed model seeks to identify and clarify the stages an SME should undertake in order to implement e-commerce more effectively and successfully within its business activities. It is further envisaged that the proposed model will allow the SME to take full advantage of the benefits to e-commerce whilst attempting to minimise or overcome the identified barriers to implementation. Design/Methodology/Approach: A total of 93 postal surveys returned from sample 500 firms; firms selected from Sunday Times Enterprise Network Business Directory and the British Chambers of Commerce Directory. In addition, 22 face-to-face semi-structured interviews were conducted across the UK from this sample examining detailed strategic and implementation issues. Fifty respondents also replied commenting on the strategic process model developed from the research, with a significant majority identifying appropriateness and ease of use. Findings: The responses were selected into two categories; “successful” and “unsuccessful”, based upon a series of strategic e-commerce criteria. Reasons for using e-commerce in the interviews were split between; innovation, natural progression, competitive pressure, the exploitation of opportunity and to a lesser extent; customer service, natural fit and differentiation. Barriers to and benefits of implementation are examined in detail for each interviewee identifying prior research, considering future expansion, considering full integration and the need for thorough planning as key factors in the implementation process. Issues following implementation were also considered as part of the model development process. Implications: The development of a detailed transferable strategic process model for e-commerce implementation amongst SMEs. The model consists of nine phases, with clear and detailed advice for the SME in terms of knowledge acquisition, identification of purpose, competitor analysis, e-commerce strategy formulation, technical delivery, promotional strategy, launch and ongoing development and analysis. Originality/Value: The creation of a transferable strategic process model for e-commerce adoption amongst SMEs, evaluated by SMEs. The transferability analysis conducted here can be considered an indicator as regards the effective use of the model by other small firms within the UK. Key Words: SME, e-commerce, adoption, transferability, process, mode

Cache-oblivious dynamic dictionaries with update/query tradeoffs

Several existing cache-oblivious dynamic dictionaries achieve O(logB N) (or slightly better O(logB N over M )) memory transfers per operation, where N is the number of items stored, M is the memory size, and B is the block size, which matches the classic B-tree data structure. One recent structure achieves the same query bound and a sometimes-better amortized update bound of O (...) memory transfers. This paper presents a new data structure, the xDict, implementing predecessor queries in O(...)worstcase memory transfers and insertions and deletions in O (...) amortized memory transfers, for any constant " with 0 < epsilon < 1. For example, the xDict achieves subconstant amortized update cost when N = ..., whereas the B-tree’s ... is subconstant only when ... is subconstant only when N = .... The xDict attains the optimal tradeoff between insertions and queries, even in the broader external-memory model, for the range where inserts cost between (...) and O(1= lg3 N) memory transfers.Danish National Research Foundation (MADALGO (Center for Massive Data Algorithmics))National Science Foundation (U.S.) (NSF Grants CCF-0541209)National Science Foundation (U.S.) (NSF Grants CCF-0541209)Computing Innovation Fellow

How cat-behavior advisors can improve clients’ willingness to adopt their advice: an investigation of advice severity, advisor credibility, and clients’ self-identity

Feline behavioral problems can be treated successfully by good advice from cat-behavior advisors, but guardians often do not comply with their advice. An experimental survey under 703 cat guardians was used to investigate what advisors can do to increase their clients’ compliance with environmental enrichment advice. By systematically varying the credibility of the advisor and the severity of their advice, the hypothesis was confirmed that highly credible advisors elicit more positive attitudes and compliance intentions than less credible advisors. Also as expected, mild advice resulted in stronger compliance intentions than severe advice because guardians believed they were better able to incorporate the required actions. Finally, guardians who more strongly thought of themselves as cat guardians were more likely to adopt the advice because they believed that other cat guardians would do the same. The investigation of factors that can increase cat guardians’ compliance with advisors’ recommendations for the treatment of behavioral problems is crucial because the wellbeing of domestic cats lies in the hands of their guardians. Several practical recommendations for cat-behavior advisors are offered.Social decision makin

Evolutionary Ecological Genomics

The recognition that evolution can happen on ecological timescales (Hairston et al. 2005; Pelletier et al. 2009; Ellner et al. 2011; Becks et al. 2012) has prompted the integration of ecology and evolution, while easier access to high-throughput sequencing technologies has increased the number of genetic nonmodel species entering the ‘omics’ era (e.g. Turner et al. 2010; Colbourne et al. 2011; Jones et al. 2012). We are now in a position to identify the genetic basis of adaptation and the mechanisms of adaptive responses in the wild. It nonetheless remains a challenge to go beyond descriptive measures of patterns of genetic variation and to identify the evolutionary processes driving species adaptation and evolution. This special issue represents a broad cross-section of research into evolutionary adaptation at the genetic level. The approaches used vary from classic QTL studies to RAD sequencing and RNAseq. Given the rapid advance of sequencing technology, we fully expect that ‘genomic’ as defined here will be merely ‘genetic’ in a few years, but we nonetheless hope that the results and methods described in this special issue will serve as a blueprint for future work in this field

A Critical Analysis of Atoh7 (Math5) mRNA Splicing in the Developing Mouse Retina

The Math5 (Atoh7) gene is transiently expressed during retinogenesis by progenitors exiting mitosis, and is essential for ganglion cell (RGC) development. Math5 contains a single exon, and its 1.7 kb mRNA encodes a 149-aa polypeptide. Mouse Math5 mutants have essentially no RGCs or optic nerves. Given the importance of this gene in retinal development, we thoroughly investigated the possibility of Math5 mRNA splicing by Northern blot, 3′RACE, RNase protection assays, and RT-PCR, using RNAs extracted from embryonic eyes and adult cerebellum, or transcribed in vitro from cDNA clones. Because Math5 mRNA contains an elevated G+C content, we used graded concentrations of betaine, an isostabilizing agent that disrupts secondary structure. Although ∼10% of cerebellar Math5 RNAs are spliced, truncating the polypeptide, our results show few, if any, spliced Math5 transcripts exist in the developing retina (<1%). Rare deleted cDNAs do arise via RT-mediated RNA template switching in vitro, and are selectively amplified during PCR. These data differ starkly from a recent study (Kanadia and Cepko 2010), which concluded that the vast majority of Math5 and other bHLH transcripts are spliced to generate noncoding RNAs. Our findings clarify the architecture of the Math5 gene and its mechanism of action. These results have implications for all members of the bHLH gene family, for any gene that is alternatively spliced, and for the interpretation of all RT-PCR experiments