This paper examines the investment behavior of research and development (R&D) under uncertainty. We assume that there is a heterogeneous effect of uncertainty on R&D investment depending on characteristics of a firm. According to the results, the size and the innovation capacity of a firm are found to positively moderate the negative relationship between uncertainty and R&D investment. When the entire sample is divided into large and small-and-medium enterprises and high innovation capacity and low innovation capacity, it is found that the innovation capacity of a firm is a more crucial factor in positively moderating the negative relationship between R&D investment and uncertainty than the size of a firm. These findings provide policy implications, particularly for small-and-medium enterprises (SMEs), to promote R&D activities.
This study analyzes how an economic recession affects entrepreneurship from a qualitative perspective. We define entrepreneur as a person who takes risks under uncertainty. Based on this definition, an entrepreneur's exit decision is modeled using real options theory to measure entrepreneur's willingness to accept uncertainty. We find that entrepreneurs who entered before a recession exit when their critical revenue stream reaches 0.16 times the average revenue stream value. The equivalent value for entrepreneurs who enter during an economic recession is 0.33 times the average revenue stream. Furthermore, when uncertainty doubles, the exit probability of entrepreneurs who enter during an economic recession is approximately 2.75 times higher than that of entrepreneurs who enter before recession. We conclude that the majority of entrepreneurs who enter during an economic recession are qualitatively disadvantaged, which leads to the overall decrease in qualitative entrepreneurship.
Background
Well analysed data from the health insurance registry allows us detailed and various analyses of a nation-wide population study. In this study, we validate the diagnostic criteria of occurrence of new cases of Inflammatory Bowel Disease (IBD) using health insurance database and investigate the epidemiological features of IBD in Korea.
Methods
A population-based clinical data of patients with IBD in the Songpa-Kangdong district of Seoul was used as reference cases and the database of National Health Insurance Service from 2005 to 2015 was retrospectively reviewed to compare the diagnostic criteria. The most accurate criterion was applied to the entire database (2002–2017) with 3-year washout period for further assessment. Non-parametric statistics and p for trend analysis were used.
Results
The most accurate criteria of new cases of IBD was the combination of the experience of colonoscopy, IBD-specific medications at least 3 months and the International Classification of Disease 10th codes for Crohn’s disease (CD) and Ulcerative colitis (UC). With this criterion, new incident cases of IBD were 40,807 (14,183 CD, 26,624 UC) during the study period. The male to female ratio of age-adjusted incidence rate was 2.5:1 for CD and 1.4:1 for UC. Age- and sex-adjusted incidence per 100,000 population of CD and UC had increased from 1.4 and 3.6 (in 2005) to 2.2 and 4.2 (in 2017). Over 13 year period, the peak incidence of CD in both male and female was between 15 and 24 years of age without significant change while the peak incidence of UC was shifted from 55–64 years (in 2005–2008) to 25–34 years of age (in 2014–2017). There was a positive correlation between the socioeconomic status and incidence of IBD (p < 0.01). The standardised incidence rates of CD and UC in metropolitan areas were 2.4 and 4.3 per 100,000 population, while that in non-metropolitan areas were 2.0 and 3.8 per 100,000 population. The incidence rate of CD in metropolitan area was still significantly higher than in non-metropolitan area after the adjustment of socioeconomic status (p = 0.03).
Conclusion
The incidence of IBD in Korea has increased over the recent decade with the shift to younger age groups. The higher incidence in higher socioeconomic status and metropolitan areas gives a clue to the aetiology of this disease.
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