Forecasting volatility: Roles of sampling frequency and forecasting horizon

This study empirically tests how and to what extent the choice of the sampling frequency, the realized volatility (RV) measure, the forecasting horizon and the time‐series model affect the quality of volatility forecasting. Using highly synchronous executable quotes retrieved from an electronic trading platform, the study avoids the influence of various market microstructure factors in measuring RV with high‐frequency intraday data and in inferring implied volatility (IV) from option prices. The study shows that excluding non‐trading‐time volatility produces significant downward bias of RV by as much as 36%. Quality of prediction is significantly affected by the forecasting horizon and RV model, but is largely immune from the choice of sampling frequency. Consistent with prior research, IV outperforms time‐series forecasts; however, the information content of historical volatility critically depends on the choice of RV measure. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark     

EXPLORING THE POTENTIAL EFFECTS OF FORECASTER MOTIVATIONAL ORIENTATION AND GENDER ON JUDGMENTAL ADJUSTMENTS OF STATISTICAL FORECASTS

The growing adoption of demand collaboration initiatives such as Collaborative Planning, Forecasting, and Replenishment (CPFR) has made judgmental adjustments of forecasts, an already widespread forecasting practice, an increasingly routine part of many logistics managers' responsibilities. This article investigates how logistics managers might improve forecast accuracy by judgmentally adjusting statistical forecasts and potential factors that may influence the effectiveness of such adjustments. In particular, our goal is to expand current knowledge in this area by focusing on individual differences, specifically motivation and gender, which have been thus far neglected in the extant literature. Our findings indicate that motivation has a significant effect on accuracy improvement and this relationship is moderated by gender. Managerial implications of these findings and future research opportunities are also presented.     

Russian enterprises in mid-2008: Characteristics of precrisis behavior

The findings of a regular survey of real sector enterprises, conducted by the Laboratory for the Analysis and Forecasting of Microeconomic Processes at the IEF, RAS, are analyzed and commented on.     

Trans‐Tasman Transmission of Government Spending Shocks

This paper investigates the international transmission of fiscal shocks between two closely‐linked, open economies. We estimate impulse response functions using a semi‐structural vector auto regressive (VAR) model and quarterly data from Australia and New Zealand for the period 1973:3–2008:4. We compare our empirical results with impulse response functions from a calibrated two‐country international real business cycle model with habit formation and adjustment costs to investment. We show that a positive shock to Australian government consumption leads to an increase in Australian output initially and then to a decline in the medium term, while the New Zealand output is negatively affected both in the short and medium term. This result is in line with the recent literature that reports beggar‐thy‐neighbour effect of positive government spending shocks.     

Length of stay and economic consequences with rivaroxaban vs enoxaparin/vitamin K antagonist in patients with DVT and PE: findings from the North American EINSTEIN clinical trial program

Objective:

Venous thromboembolism (VTE) (deep vein thrombosis [DVT] and pulmonary embolism [(PE]) represents a substantial economic burden to the healthcare system. Using data from the randomized EINSTEIN DVT and PE trials, this North American sub-group analysis investigated the potential of rivaroxaban to reduce the length of initial hospitalization in patients with acute symptomatic DVT or PE.

Methods:

A post-hoc analysis of hospitalization and length-of-stay (LOS) data was conducted in the North American sub-set of patients from the randomized, open-label EINSTEIN trial program. Patients received either rivaroxaban (15?mg twice daily for 3 weeks followed by 20?mg once daily; n?=?405) or dose-adjusted subcutaneous enoxaparin overlapping with (guideline-recommended ‘bridging’ therapy) and followed by a vitamin K antagonist (VKA) (international normalized ratio?=?2.0–3.0; n?=?401). The open-label study design allowed for the comparison of LOS between treatment arms under conditions reflecting normal clinical practice. LOS was evaluated using investigator records of dates of admission and discharge. Analyses were carried out in the intention-to-treat population using parametric tests. Costs were applied to the LOS based on weighted mean cost per day for DVT and PE diagnoses obtained from the Healthcare Cost and Utilization Project dataset.

Results:

Of 382 patients hospitalized, 321 (84%), had acute symptomatic PE; few DVT patients required hospitalization. Similar rates of VTE patients were hospitalized in the rivaroxaban and enoxaparin/VKA treatment groups, 189/405 (47%) and 193/401 (48%), respectively. In hospitalized VTE patients, rivaroxaban treatment produced a 1.6-day mean reduction in LOS (median?=?1 day) compared with enoxaparin/VKA (mean?=?4.5 vs 6.1; median?=?3 vs 4), translating to total costs that were $3419 lower in rivaroxaban-treated patients.

Conclusion:

In hospitalized North American patients with VTE, treatment with rivaroxaban produced a statistically significant reduction in LOS. When treating DVT and PE patients, clinicians should consider newer anti-coagulants with less complex treatment regimens.     

Variety,Globalization, and Social Efficiency

The standard formal presentation of the Dixit‐Stiglitz‐Krugman (DSK) model of monopolistic competition with a constant‐elasticity‐of‐substitution (CES) utility function supposes a sufficient number of firms so that the elasticity of demand facing each variety is approximated by a constant elasticity of substitution. Such a formulation forces economies of scale to be frozen so that firm size never changes. We use a Bertrand‐Nash interpretation of the equilibrium that allows the elasticity of demand facing each variety to depend on the number of varieties, thus allowing the gains from globalization to reflect both the increase in variety and the exploitation of economies of scale. We also develop a precise expression for per capita real income with any number of sectors and examine the age‐old question of the socially optimal number of varieties.     

Studies in insurance mathematics

Abstract

In the new Rules of Calculation of the Life Insurance Co. Framtiden, the old idea of the continuous mode of payment has been realized. In practice, this method only signifies, that the premium is to be restored for the time elapsed after the moment of death. Theoretically, it makes unnecessary the computation of premiums by the aid of (exact or approximate) yearly, half-yearly, quarterly and monthly annuities, continuous annuities being solely needed. It may perhaps be of interest to give a more detailed account of the method employed.