Which Survey Indicators Are Useful for Monitoring Consumption? Evidence fron European Countries

This paper assesses the information content of two survey indicators for consumption developments in the near future for eight European countries in the period 1985-1998. Empirical work on this topic typically focuses on consumer confidence, the perceptions of buyers of consumption goods. This paper examines whether perceptions of sellers of consumption goods, measured by retail trade surveys, may also improve short-term monitoring of consumption. We find that both consumer confidence and retailer confidence embody valuable information, when analyzed in isolation. For France, Italy and Spain we conclude that adding retail confidence does not improve the indicator model once consumer confidence has been included. For the UK the reverse case is obtained. For the remaining four countries we show that combining consumer sentiment and retail trade confidence into a composite indicator leads to optimal results. Our results suggest that incorporating information from retail trade surveys may offer significant benefits for the analysis of short-term prospects of consumption.consumption; consumer confidence; retail trade confidence; composite indicators

Segment selection by relationship strength

Relationship management is becoming more important, also in direct marketing. Measuring the strength of relationships is relevant, since relationship strength can be used as a segmentation variable. However, in measuring relationship strength, mostly one or more behavioral indicators are used (e.g. the R/F/M-formula). So, these indicators measure customer quality instead of relationship quality, which is mainly determined by customer perceptions. This paper shows some preliminary results of a relationship audit, which depends on customer attitudes towards the relationship.marketing ;

Achievement test construction using 0-1 linear programming

In educational testing the work of professional test agencies has shown a trend towards item banking. Achievement test construction is viewed as selecting items from a test item bank such that certain specifications are met. As the number of possible tests is large and practice usually imposes various constraints on the selection process, a mathematical programming approach is obvious. In this paper it is shown how to formulate achievement test construction as a 0¿1 linear programming problem. A heuristic for solving the problem is proposed and two examples are given. It is concluded that a 0¿1 linear programming approach fits the problem of test construction in an appropriate way and offers test agencies the possibility of computerizing their services

Economic growth, income distribution, and poverty in Poland during transition

The authors attempt to analyze the linkages between macroeconomic policies and economic growth variables, their movement over time, and their impact on poverty in the case of Poland. Poland, a middle-income country, is of particular interest because its data sources allow for a relatively detailed analysis of such developments, and the macroeconomic environment and the economic growth variables show a relatively sizable degree of variance. In addition, Poland has struggled in the past few years to reduce poverty while still experiencing positive economic growth. The authors show that in Poland, poverty-reducing growth depends heavily on the ability of the economy to generate jobs. During the early years of transition, net job growth was positive, while after the Russian crisis of 1998, productivity gains were accomplished mostly through labor shedding, henceforth, increasing poverty in Poland. In addition, the authors identify how fiscal and social protection policies affect income distribution and poverty in Poland.Economic Theory&Research,Environmental Economics&Policies,Services&Transfers to Poor,Poverty Impact Evaluation,Economic Conditions and Volatility,Inequality,Governance Indicators,Environmental Economics&Policies,Achieving Shared Growth,Economic Theory&Research

Identification of ‘wasteful commuting’ using search theory

In this paper, we employ search theory as a micro-economic foundation for the wasteful commuting hypothesis. In the empirical analysis, the extent of the ‘wasteful commuting’ is identified by comparing the commute of employees and self-employed individuals who do not work from home. It is argued that the commute of the self-employed is the result of a search process for vacant workplaces, whereas employees search for vacant jobs. Because the arrival rate of workplaces exceeds the arrival rate of jobs, the self-employed have a shorter commute. We find that 35% of the commuting time may be considered ‘wasteful’ and reject alternative hypotheses why the self-employed have a shorter commute.

Runaway and walkaway stars from the ONC with Gaia DR2

Theory predicts that we should find fast, ejected (runaway) stars of all masses around dense, young star-forming regions. $N$-body simulations show that the number and distribution of these ejected stars could be used to constrain the initial spatial and kinematic substructure of the regions. We search for runaway and slower walkaway stars within 100 pc of the Orion Nebula Cluster (ONC) using $Gaia$ DR2 astrometry and photometry. We compare our findings to predictions for the number and velocity distributions of runaway stars from simulations that we run for 4 Myr with initial conditions tailored to the ONC. In $Gaia$ DR2, we find 31 runaway and 54 walkaway candidates based on proper motion, but not all of these are viable candidates in three dimensions. About 40 per cent are missing radial velocities, but we can trace back 9 3D-runaways and 24 3D-walkaways to the ONC, all of which are low/intermediate-mass (<8 M$_{\odot}$). Our simulations show that the number of runaways within 100 pc decreases the older a region is (as they quickly travel beyond this boundary), whereas the number of walkaways increases up to 3 Myr. We find fewer walkaways in $Gaia$ DR2 than the maximum suggested from our simulations, which may be due to observational incompleteness. However, the number of $Gaia$ DR2 runaways agrees with the number from our simulations during an age of $\sim$1.3-2.4 Myr, allowing us to confirm existing age estimates for the ONC (and potentially other star-forming regions) using runaway stars.Comment: 19 pages, 7 figures, accepted for publication in MNRA

Partial separability and entanglement criteria for multiqubit quantum states

We explore the subtle relationships between partial separability and entanglement of subsystems in multiqubit quantum states and give experimentally accessible conditions that distinguish between various classes and levels of partial separability in a hierarchical order. These conditions take the form of bounds on the correlations of locally orthogonal observables. Violations of such inequalities give strong sufficient criteria for various forms of partial inseparability and multiqubit entanglement. The strength of these criteria is illustrated by showing that they are stronger than several other well-known entanglement criteria (the fidelity criterion, violation of Mermin-type separability inequalities, the Laskowski-\.Zukowski criterion and the D\"ur-Cirac criterion), and also by showing their great noise robustness for a variety of multiqubit states, including N-qubit GHZ states and Dicke states. Furthermore, for N greater than or equal to 3 they can detect bound entangled states. For all these states, the required number of measurement settings for implementation of the entanglement criteria is shown to be only N+1. If one chooses the familiar Pauli matrices as single-qubit observables, the inequalities take the form of bounds on the anti-diagonal matrix elements of a state in terms of its diagonal matrix elements.Comment: 25 pages, 3 figures. v4: published versio

Spring migration of Ruffs Philomachus pugnax in Fryslân: estimates of staging duration using resighting data

Seasonal bird migration involves long flights, but most time is actually spent at intermediate staging areas. The duration of stay at these sites can be evaluated with mark–recapture methods that employ day-to-day local encounters of individually marked birds. Estimates of staging duration are based on two probabilities: the immigration probability, the complement of a bird’s seniority to an area, and the emigration probability, the complement of the staying probability. Estimating total staging duration from seniority and staying probabilities requires validation for resighting data and here we compare three data categories of Ruffs Philomachus pugnax passing through The Netherlands during northward migration: (1) newly colour-ringed, (2) previously colour-ringed and (3) radio-tagged Ruffs (recorded by automated receiving stations). Between 2004 and 2008, 4363 resighting histories and 95 telemetry recording histories were collected. As sample sizes for females were low, only data for males were analysed. Possible catching effects affecting estimates of staging duration were explored. Staying probability was estimated for all data. Seniority however, could not be estimated for newly marked Ruffs; the assumption of equal ‘capture’ probability for reverse-time models applied to estimate seniority is violated for seasonal resighting histories starting with a catching event. Therefore, estimates of total staging duration were based on resightings of previously colour-marked birds only. For radio-tagged birds a minimal staging duration (time between tagging and last recording) was calculated. Modelling indicated that newly colour-ringed birds had a higher staying probability than previously colour-ringed birds, but the difference translated to a prolonged staging duration in newly ringed birds of only 0.4–0.5 d, suggesting a very small catching effect. The minimal staging duration of radio-tagged birds validated estimates of staging duration for colour-ringed birds in 2007 but not in 2005. In 2005 a low resighting probability resulted in underestimates of staging duration. We conclude that (1) estimates of staying probability can be affected by catching although effects on staging duration might be small, and that (2) low resighting probabilities can lead to underestimates in staging duration. In our study previously ringed Ruffs resighted in 2006–08 yielded reliable estimates of staging duration as data had sufficiently high resighting probabilities. Average staging durations varied between 19 d in 2008 and 23 d in 2006.

Methods and models for the construction of weakly parallel tests

Several methods are proposed for the construction of weakly parallel tests [i.e., tests with the same test information function (TIF)]. A mathematical programming model that constructs tests containing a prespecified TIF and a heuristic that assigns items to tests with information functions that are equal are important components of these methods. Numerical examples demonstrate that tests can be constructed quickly and that the heuristic produces good results. However, the heuristic is not applicable for every set of practical constraints (e.g., constraints with respect to test administration time, test composition, or dependencies between items). Index terms: item banking, heuristics, mathematical programming, test construction, weakly parallel tests