Wikipedia’s open content production platform createssignificant spillover benefits that encourage users to contributefurther

Many organisations are developing open platforms to create, store and share knowledge. Aleksi Aaltonen and Stephan Seiler analyse editing data by Wikipedia users to show how content creation by individuals generates significant ‘spillover’ benefits, encouraging others to contribute to the collective process of knowledge production

How taking a bit longer to do your shopping might save you money

To what extent can shoppers convert the time they spend looking for particular products into monetary savings? Using electronic tags to study the behavior of 12,000 consumers in a large supermarket in Northern California, Fabio Pinna and Stephan Seiler find that consumers can save up to $11 per shopping trip just by searching longer for products

Cumulative growth in user-generated content production : evidence from Wikipedia

Open content production platforms typically allow users to gradually create content and react to previous contributions. Using detailed edit-level data across a large number of Wikipedia articles, we investigate how past edits shape current editing activity. We find that cumulative past contributions, embodied by the current article length, lead to signifi- cantly more editing activity, while controlling for a host of factors such as popularity of the topic and platform-level growth trends. The magnitude of the effect is large; content growth over an eight-year period would have been 45% lower in its absence. Our findings suggest other open content production environments are likely to also benefit from similar cumulative growth effects. In the presence of such effects, managerial interventions that increase content are amplified because they trigger further contributions

Consumer search: evidence from path-tracking data

We estimate the effect of consumer search on the price of the purchased product in a physical store environment. We implement the analysis using a unique data set obtained from radio frequency identification tags, which are attached to supermarket shopping carts. This technology allows us to record consumers' purchases as well as the time they spent in front of the shelf when contemplating which product to buy, giving us a direct measure of search effort. Controlling for a host of confounding factors, we estimate that an additional minute spent searching lowers price paid by $2.10 which represents 8 percent of average trip-level expenditure

The Impact of Competition on Management Quality: Evidence from Public Hospitals

We analyze the causal impact of competition on managerial quality (and hospital performance). To address the endogeneity of market structure we analyze the English public hospital sector where entry and exit are controlled by the central government. Because closing hospitals in areas where the governing party is expecting a tight election race ("marginals") is rare due to the fear of electoral defeat, we can use political marginality as an instrumental variable for the number of hospitals in a geographical area. We find that higher competition is positively correlated with management quality, measured using a new survey tool. Adding a rival hospital increases management quality by 0.4 standard deviations and increases survival rates from emergency heart attacks by 8.8%. We confirm the validity of our IV strategy by conditioning on marginality in the hospital's own catchment area, thus identifying purely off the marginality of rival hospitals. This controls for "hidden policies" that could be used in marginal districts to improve hospital management. We also run placebo tests of marginality on schools, a public service where the central government has no formal influence on market structure.management, hospitals, competition, productivity

The Impact of Competition on Management Quality: Evidence from Public Hospitals

In this paper we examine the causal impact of competition on management quality. We analyze the hospital sector where geographic proximity is a key determinant of competition, and English public hospitals where political competition can be used to construct instrumental variables for market structure. Since almost all major English hospitals are government run, closing hospitals in areas where the governing party has a small majority is rare due to fear of electoral punishment. We find that management quality - measured using a new survey tool - is strongly correlated with financial and clinical outcomes such as survival rates from emergency heart attack admissions (AMI). More importantly, we find that higher competition (as indicated by a greater number of neighboring hospitals) is positively correlated with increased management quality, and this relationship strengthens when we instrument the number of local hospitals with local political competition. Adding another rival hospital increases the index of management quality by one third of a standard deviation and leads to a 10.7% reduction in heart-attack mortality rates.management, hospitals, competition, productivity

Management practices in the NHS

CEP researchers have conducted a unique survey of clinicians and hospital managers to explore how well NHS hospitals are managed

Quantifying spillovers in open source content production: evidence from Wikipedia

Using detailed edit-level data over eight years across a large number of articles on Wikipedia, we find evidence for a positive spillover effect in editing activity. Cumulative past contributions, embodied by the current article length, lead to significantly more editing activity, while controlling for a host of factors such as popularity of the topic and platform-level growth trends. The magnitude of the externality is significant, and growth in editing activity on the average article would have been about 50% lower in its absence. The spillover operates through an increase in the number of contributing users, whereas the length of contributions remains unchanged. Edits triggered by spillovers involve only marginally more deletion and replacement of content than the average edit, suggesting that past contributions do inspire the creation of new content rather than corrections of past mistakes. Roughly 75% of the spillover is due to new rather than returning users contributing content

Kinesin and dynein mutants provide novel insights into the roles of vesicle traffic during cell morphogenesis in Neurospora

AbstractBackground: Kinesin and cytoplasmic dynein are force-generating molecules that move in opposite directions along microtubules. They have been implicated in the directed transport of a wide variety of cellular organelles, but it is unclear whether they have overlapping or largely independent functions.Results: We analyzed organelle transport in kinesin and dynein single mutants, and in a kinesin and dynein double mutant of Neurospora crassa. Remarkably, the simultaneous mutation of kinesin and dynein was not lethal and resulted in an additive phenotype that combined the features of the single mutants. The mutation of kinesin and dynein had opposite effects on the apical and retrograde transport, respectively, of vesicular organelles. In the kinesin mutant, apical movement of submicroscopic, secretory vesicles to the Spitzenkörper – an organelle in the hyphal apex – was defective, whereas the predominantly retrograde movement of microscopic organelles was only slightly reduced. In contrast, the dynein mutant still had a prominent Spitzenkörper, demonstrating that apical transport was intact, but retrograde transport was essentially inhibited completely. A major defect in vacuole formation and dynamics was also evident. In agreement with the observations on apical transport, protein secretion into the medium was markedly inhibited in the kinesin mutant but not in the dynein mutant.Conclusions: Transport of secretory vesicles is necessary but not sufficient for normal apical extension. A component of retrograde transport, presumably precursors of the vacuole system, is also essential. Our findings provide new information on the role microtubule motors play in cell morphogenesis and suggest that kinesin and cytoplasmic dynein have largely independent functions within separate pathways