Non-Negativity of Nominal and Real Riskless Rates, Arbitrage Theory, and the Null-Alternative Cash

Pragmatic-world nominal riskless rates are non-negative. However, conventional arbitrage theory has yet to develop a theoretical justification of this phenomenon. – We define the null-alternative cash as an investor holding onto cash and refraining from investment and consumption ("doing nothing"); we use the null-alternative cash to prove that both nominal spot and nominal forward rates are non-negative and that prices of zero-coupon bonds do not increase with increasing maturity. In a positive inflation environment, however, both real spot and real forward rates might well become negative, but prices of zero-coupon bonds still do not increase with increasing maturity. --arbitrage theory,inflation,non-negativity of spot and forward rates,short selling constraints

Some economic remarks on arbitrage theory

Today's primarily mathematically oriented arbitrage theory does not address some economically important aspects of pricing. These are, first, the implicit conjecture that there is 'the' price of a portfolio, second, the exact formulation of no-arbitrage, price reproduction, and positivity of the pricing rule under short selling constraints, third, the explicit assumption of a nonnegative riskless interest rate, and fourth, the connection between arbitrage theory (that is almost universal pricing theory) and special pricing theories. Our article proposes the following answers to the above issues: The first problem can be solved by introducing the notion of 'physical' no-arbitrage, the second one by formulating the concept of 'actively' traded portfolios (that is non-dominated portfolios) and by requiring that there is a minimum price for actively traded portfolios and therefore for every admissible portfolio, and the third one by combining the 'invisible' asset 'cash' with the idea of actively traded portfolios - a riskless asset with a rate of return less than zero can never be actively traded in the presence of cash. Finally, the connection between arbitrage theory and special pricing theories ('law-of-one-price-oriented' and 'utility-oriented' pricing) consists in the fact that special pricing theories merely concretize arbitrage theory using different assumptions. --

Risikoabschläge, Risikozuschläge und Risikoprämien: Finanzierungstheoretische Anmerkungen zu einem Grundproblem der Unternehmensbewertung

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Das Gaußsche Zinsstrukturmodell: Eine Analyse auf der Basis von Wahrscheinlichkeitsverteilungen

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Unternehmensbewertung: Eine finanzmarkttheoretische Untersuchung

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Falscher Mehltau an Gurken – Regulierungsmöglichkeiten im ökologischen Freilandgemüseanbau und unter Glas

To increase the yield of organically grown cucumber a lot of investigations were carried out in the last years. The influence of sowing and planting was compared and the susceptibility of different varieties as well as the influence of plant extracts was investigated in field trials. Planting resulted in an earlier harvest with a higher yield. Further effort in breeding resistant varieties with higher yield is needed. Also, the efficacy of plant strengthening products and plant extracts must still be improved. Regulation by specific climate strategy under glass was successful to avoid or delay the infection with Pseudoperonosproa cubensis

Validierung von Feldstärke - Messplätzen im Frequenzbereich von 9 kHz – 30 MHz mit Rahmen-Antennen

In den letzten zwei Jahren wurde in der Ad Hoc < 30 MHz im CISPR A an der Ausarbeitung einer Beschreibung der Validierungsmethode und der Messmethode gearbeitet. Sowohl für die Validierungsmethode, als auch für die Messung von Prüflingen liegen mittlerweile Beschreibungen in Form von Entwürfen vor. Diese Entwürfe wurden im CISPR zur Diskussion gestellt und kommentiert. Nach wie vor ist die Einführung einer Validierungsmethode von Messplätzen im Frequenzbereich von 9 kHz bis 30 MHz eine fordernde Aufgabe. Der Round Robin Test (RRT) in 2011, durchgeführt vom AK 767.4.1 (AHF) hat zwar zur Information über das Verhalten von Prüfplätzen bei Anwendung einer gewissen Messmethode geführt, aber auch viele Fragen aufgeworfen. Der Artikel stellt den erarbeiteten Stand des Entwurfes zur Validierung dar und zeigt den weiteren Untersuchungsbedarf