Asymmetric output gap effects in Phillips Curve and mark-up pricing models: evidence for the US and the UK

A number of studies have found an asymmetric response of consumer price index inflation to the output gap in the US in simple Phillips curve models. We consider whether there are similar asymmetries in mark-up pricing models, that is, whether the mark-up over producers' costs also depends upon the sign of the (adjusted) output gap. The robustness of our findings to the price series is assessed, and also whether price-output responses in the UK are asymmetric.

Mark Casson: the Entrepreneur at 30 -continued relevance?

Mark Casson's The Entrepreneur: An Economic Theory (1982) has become one of the most influential books in the field of entrepreneurship. For the first time, this article outlines its origins and summarizes its main themes. The article goes on to show how Casson's subsequent research has closely followed the research agenda he set for himself in The Entrepreneur and illustrates the continuing challenge his work presents to entrepreneurship scholars. The article is based on an interview the authors conducted with Mark Casson on the thirtieth anniversary of the book's publication. Copyright © 2014 Strategic Management Society.

Persistence in diving American mink

Background American mink forage on land and in water, with aquatic prey often constituting a large proportion of their diet. Their long, thin body shape and relatively poor insulation make them vulnerable to heat loss, particularly in water, yet some individuals dive over 100 times a day. At the level of individual dives, previous research found no difference in dive depth or duration, or the total number of dives per day between seasons, but mink did appear to make more dives per active hour in winter than in summer. There was also no difference in the depth or duration of individual dives between the sexes, but there was some evidence that females made more dives per day than males. However, because individual mink dives tend to be extremely short in duration, persistence (quantified as the number of consecutive dives performed) may be a more appropriate metric with which to compare diving behaviour under different scenarios. Results Mink performed up to 28 consecutive dives, and dived continually for up to 36 min. Periods of more loosely aggregated diving (termed ‘aquatic activity sessions’) comprised up to 80 dives, carried out over up to 162.8 min. Contrary to our predictions, persistence was inversely proportional to body weight, with small animals more persistent than large ones, and (for females, but not for males) increased with decreasing temperature. For both sexes, persistence was greater during the day than during the night. Conclusions The observed body weight effect may point to inter-sexual niche partitioning, since in mink the smallest animals are females and the largest are males. The results may equally point to individual specialism’s, since persistence was also highly variable among individuals. Given the energetic costs involved, the extreme persistence of some animals observed in winter suggests that the costs of occasional prolonged activity in cold water are outweighed by the energetic gains. Analysing dive persistence can provide information on an animal’s physical capabilities for performing multiple dives and may reveal how such behaviour is affected by different conditions. Further development of monitoring and biologging methodology to allow quantification of hunting success, and thus the rewards obtained under alternative scenarios, would be insightful.

Mushrooms and taphonomy: the fungi that mark woodland graves

Two closely related chemoecological groups of fungi, the ammonia fungi and the postputrefaction fungi, have been associated with the decomposition by-products of cadavers. Sporocarps have been observed in disparate woodlands across the world and often mark sites of graves. These groups of fungi provide visible markers of the sites of cadaver decomposition and follow repeated patterns of successional change as apparent decomposition proceeds. We suggest these phenomena may become a useful tool for crime scene investigation, forensic archaeology and forensic taphonomy.

Ståndortsindex och produktion för björk och gran på samma mark

På 11 lokaler där björk och gran vuxit i bestånd intill varandra på likartad mark uppskattades ståndortsindex (SI) för gran och björk med hjälp av brösthöjdsålder och höjd på övrehöjdsträd. På 22 lokaler (11 verkliga, 11 simulerade) uppskattades SI för gran och björk med hjälp av ståndortsegenskaper. Sambandet mellan SI för gran och för vårtbjörk sammanfattas i en tabell där SI G24 motsvarar B23 och SI G36 motsvarar B26. Marker där vårtbjörken kan konkurrera med granen i produktion bör vara friska lågörttyper med markvattenklass S eller K. Hög höjd över havet och nordliga breddgrader har också mer negativ påverkan på björkens än på granens tillväxt. På breddgrad 60-61 ºN  upp till 100 m över havet uppskattas då SI för björk till B24-26 och för gran till G25-27. På de lägre boniteterna (B23/G24) beräknas volymsproduktionen vara likvärdig för vårtbjörk och gran, medan på de högre boniteterna (B26/G36) beräknas granens medelvolyms-produktion vara upp mot dubbelt så hög som för vårtbjörk. Vårtbjörkens torrsubstansproduktion beräknas däremot överstiga den för gran på de lägre boniteterna och uppgå till ca 80% av granens torrsubstansproduktion på de högre boniteterna.  Materialet i studien är begränsat och försiktighet bör iakttagas vid generaliseringar.

O Impacto da Abertura Comercial Sobre Mark-Up e Produtividade Industrial Brasileira

Rio de Janeiro