In this paper we characterize the "price of anarchy", i.e., the inefficiency between user and system optimal solutions, when costs are non-separable, asymmetric and nonlinear, generalizing earlier work that has addressed "price of anarchy" under separable costs. The generalization models traffice equilibria, competitive multi-period pricing and competitive supply chains. The bounds established in the paper are tight and explicitly account for the degeee of asymmetry and nonlinearity of the cost function. We introduce and alternate proof method for providing bounds that uses ideas from semidenfinite optimization. Finally, in the context of nulti-period pricing our analysis establishes that user and system optimal soulutions coincide.

Företaget Rebtel ville ha en ny landningssida som riktade sig till internationella studenter. Denna sida skulle vara optimerad för målgruppen både gällande design och innehåll. En förundersökningen bestående av bland annat intervjuer med målgruppen, målgruppsanalyser och research gjordes därför. Förundersökningen bestod också av intervjuer med olika roller på företaget Rebtel för att få en inblick i olika arbetsrollers perspektiv och uppgifter under en sådan process. Med hjälp av förundersökningens fynd togs skisser fram och en landningssida utvecklades bland annat genom programmeringsspråken HTML5, CSS3, LESS, JavaScript, .NET och C#. Resultatet blev en landningssida på tre språk: Engelska, Franska och Spanska. En särskild rapport med resultat från intervjuer, utveckling med mera levererades även till Rebtel. / The company Rebtel wanted a new landing page that was aimed at international students. This page would be optimized for the target group in terms of both design and content. An investigation including interviews with the target audience, target user analysis and research were made. The investigation also consisted of interviews with various roles at the company Rebtel, to get an insight into their perspectives and tasks during this kind of process. Using the findings from these investigations sketches were made and a landing page was developed through the programming languages HTML5, CSS3, LESS, JavaScript, .NET and C#. The result was a landing page in three languages: English, French and Spanish. A special report with results from interviews and development was also delivered to Rebtel.