This paper examines the overlap between competition and friendship in networks, an instance of multiplexity that we call the grand duality. We demonstrate that managers differ systematically whether they perceive competition with their friends. Structure matters, in that managers are more likely to see competition among friends who are the same sex, in the same work unit, on the same social ran...

Systems engineering is a discipline with methods and techniques to address complex problems. We want to study how Systems Engineering methods can help to address today’s grand challenges, such as the energy problem. The first step is problem definition which aims at articulating the problem in its context as clearly as possible. Humanity will have to cope with the energy problem, one of the mos...

I revisit the question of whether entrepreneurs face liquidity constraints in business formation. The principle challenge is that wealth is correlated with unobserved ability, and adequate instruments are often difficult to identify. This paper uses the son’s birth order as an instrument for household wealth. The instrument would likely not be useful in Western data, but it is in many non-Weste...

Knowledge is limited on mortality of grand multiparous women ( 5 deliveries), whose hormonal, metabolic, and social conditions differ from the average. The authors studied overall and cause-specific mortality in 1974–2001 among 87,922 grand multiparous women including 3,678 grand grand multiparous women ( 10 deliveries) in Finland. Standardized mortality ratios were defined as ratios of observe...

Repeated deliveries might disturb the levator function and increase defecation disorders. In this prospective study, we determined the electric activity of the levator ani muscle (LAM) in nullipara, multipara, grand multipara, and great grand multipara (20 subjects for each group). Multiparity, grand multiparity, and great grand multiparity were defined as women having 2 - 5, 6 - 9, and 10 and ...

This paper presents the Golem Group/University of California at Los Angeles entry to the 2005 DARPA Grand Challenge competition. We describe the main design principles behind the development of Golem 2, the race vehicle. The subsystems devoted to obstacle detection, avoidance, and state estimation are discussed in more detail. An overview of vehicle performance in the field is provided, includi...