Universal Soft Terms in the MSSM on D-branes

In Type II string vacua constructed from intersecting/magnetized D-branes, the supersymmetry-breaking soft terms are genericaly non-universal. It is shown that universal supersymmetry-breaking soft terms may arise in a realistic MSSM constructed from intersecting/magnetized D-branes in Type II string theory. For the case of dilaton-dominated supersymmetry-breaking, it is shown that the universal scalar mass and trilinear coupling are fixed such that $m_0=(1/2)m_{3/2}$ and $A_0 = - m_{1/2}$. In addition, soft terms where the universal scalar mass $m_0$ is much larger than the universal gaugino mass $m_{1/2}$ may be easily obtained within the model, corresponding to the Focus Point (FP)/Hyperbolic Branch (HB) regions of the mSUGRA/CMSSM parameter space. Finally, it is shown that the special dilaton and no-scale strict moduli boundary conditions, which are well-known in heterotic string constructions, may also be obtained.Comment: Version published in Nuclear Physics

Learning relationships from theory to design

This paper attempts to bridge the psychological and anthropological views of situated learning by focusing on the concept of a learning relationship, and by exploiting this concept in our framework for the design of learning technology. We employ Wenger's (1998) concept of communities of practice to give emphasis to social identification as a central aspect of learning, which should crucially influence our thinking about the design of learning environments. We describe learning relationships in terms of form (one‐to‐one, one‐to‐many etc.), nature (explorative, formative and comparative), distance (first‐, second‐order), and context, and we describe a first attempt at an empirical approach to their identification and measurement

The Value of Publishing Official Central Bank Forecasts

The aim of the present analysis is to shed light on the question whether Central Banks should publish their macroeconomic forecasts, and what could possibly be gained in monetary policy if they did so. We show that disclosing the Central Bank’s assessment of the prevailing inflationary pressures in the form of a forecast improves macroeconomic performance even if this assessment is imprecise. This is because it makes policy more predictable. We are also interested in finding out the useful content of the forecasts, if published, and answering the question whether it makes a difference if these official forecasts are “unconditional” in the sense of incorporating the Central Bank’s forecasts of its own policy as well, or “conditional” on some other policy assumption. Possible conditional alternatives may include assuming unchanged instruments, however specified, or assuming the kind of policy that the private sector is estimated to expect. The analysis comes out in favour of publishing unconditional forecasts, which reveal the intended results of monetary policy. A discussion of some practical issues related to publishing official macroeconomic forecasts is also provided.forecasting; transparency; monetary policy; central banks

Financial conditions indexes

This paper provides an exposition of the nature, means of estimation and uses of Financial Conditions Indexes (FCIs) and their relationship to the more common Monetary Conditions Indexes (MCIs) that are used by market analysts, international organisations and central banks. Using panel datasets for Western Europe we explore how asset prices, particularly house and stock prices, can provide useful additional indicators of future changes in output and inflation. We find a clear role for house prices but a poorly determined relationship for stock prices. Unfortunately the most useful role for FCIs comes from their incorporation of high frequency data and the opportunity this gives for extracting information about changes in market expectations for inflation and output. This helps market participants make judgements about likely central bank reactions and helps central banks assess the stance of policy between forecasts. While stock prices are high frequency, house prices are not. At quarterly frequency central banks in particular will want to use traditional economic forecasting methods and summary indicators like FCIs will have only a limited role. We illustrate how such an FCI can be used, drawing on monthly data for Finland.financial conditions; asset prices; house prices; stock prices

The use of real-time information in Phillips curve relationships for the euro area

The dynamics of the Phillips Curve in New Keynesian, Expectations Augmented and Hybrid forms are extremely sensitive to the choice, timing and restrictions on variables. An important element of the debate revolves round what information decision-makers took into account at the time and round what they thought was going to happen in the future. The original debate was conducted using up to date, revised estimates of the data as in the most recent official publications. In this paper, however, we explore how much three aspects of the specification of the information available at the time affect the performance of the various Phillips curves and the choice of the most appropriate dynamic structures. First we consider the performance of forecasts, published at the time, as representations of expectations. Second, we explore the impact of using 'real time data' in the sense of what were the most recently available estimates of the then present and past. Finally we review whether it helps to use the information that was available at the time in the choice of instruments in the estimation of the relationships rather than the most up to date estimate of the data series that has been published. Thus different datasets are required in the instrument set for every time period. We use a single consistent source for 'real-time' data on the past, estimates of the present and forecasts, from OECD Economic Outlook and National Accounts. We set this up as a panel for the euro area countries covering the period since 1977. The OECD publishes forecasts twice a year, which permits a more detailed exploration of the importance of the timing of information. Our principal conclusions are (1) that the most important use of real time information in the estimation of the Phillips curve is in using forecasts made at the time to represent expectations; (2) real time data indicate that the balance of expectations formation was more forward than backward-looking; (3) by contrast using the most recent, revised, data suggests more backward-looking and less well-determined behaviour. --real-time data,Phillips curve,euro area