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SummaryThe paper analyses longitudinal Compustat data on dividend payments and share repurchases of over 2000 US industrial firms by using 2-yearly averages for the period 1992–2007. First, dynamic auto-regressive models for dividends and share repurchases were estimated by maximum likelihood to yield consistent and efficient estimates. Second, because firms pay dividends at different rates, comprehensive dynamic and static random-effects models for dividends were estimated. Third, models were estimated for share repurchases and the interrelationships between dividends and repurchases were investigated, tackling endogeneity issues. The results showed that dividend decisions are likely to precede those regarding share repurchases, and higher dividend payments decreased the magnitudes of repurchases; the effects of repurchases on dividends were generally insignificant.

The paper examines the capital structure adjustment dynamics of listed non-financial corporations in seven east Asian countries before, during and after the crisis of 1997–1998. Our methodology allows for speeds of adjustment to vary, not only among firms, but also over time, distinguishing between cases of sudden and smooth adjustment.Whereas, compared with firms in the least affected countries, average leverages were much higher, generalized method-ofmoments analysis of the Worldscope panel data suggests that average speeds of adjustment were lower in the worst affected countries. This holds also for the severely financially distressed firms in some worst affected countries, though the trend reversed in the post-crisis period. These findings have important implications for the regulatory environment as well as access to market finance.

SummaryWe review some prospective scan-based methods that are used in health-related applications to detect increased rates of mortality or morbidity and to detect bioterrorism or active clusters of disease. We relate these methods to the use of the moving average chart in industrial applications. Issues that are related to the performance evaluation of spatiotemporal scan-based methods are discussed. In particular we clarify the definition of a recurrence interval and demonstrate that this measure does not reflect some important aspects of the statistical performance of scan-based, and other, surveillance methods. Some research needs in this area are given.

Summary Free-choice profiling is a technique that is used in sensory studies whereby assessors are allowed to describe products by using their own preferred descriptors and own number of descriptors. We show how a study of this type on eight varieties of port wine can be analysed and, in particular, how to associate the descriptors of the wines with each assessor and with a group average representation. We show how biplots combined with generalized orthogonal Procrustes analysis can be constructed and used to explore consistencies and idiosyncrasies among assessors’ uses of their descriptors and scales.

Summary Because exposure to radon gas in buildings is a likely risk factor for lung cancer, estimation of residential radon levels is an important public health endeavour. Radon originates from uranium, and therefore data on the geographical distribution of uranium in the Earth's surface may inform about radon levels. We fit a Bayesian geostatistical model that appropriately combines data on uranium with measurements of indoor home radon in the state of Iowa, thereby obtaining more accurate and precise estimation of the geographic distribution of average residential radon levels than would be possible by using radon data alone.

SUMMARY Although Simes' modification of the Bonferroni procedure tends to perform very well, albeit often being slightly liberal for negatively dependent hypotheses, there are special cases where it fails more dramatically. We prove that these special cases are indeed special, applying only to specific significance levels, and obtain a strong bound on the average deviation of the Simes corrected P-value from the true probability over any interval of P-values. From this, it is argued that Simes' procedure should be expected to perform well except for pathological examples.

SummaryStudying spending over time requires reliable data. It is not clear that such data exist in the UK, however. The two published sources of functional spending numbers—the Office for National Statistics's ‘blue book’ and Her Majesty's Treasury's Public Expenditure Statistical Analyses (PESA)—rely on estimates of past spending, using a link year method, rather than recalculating actual spending figures when functional definitions change. We assess the various measures of spending in the UK. Specifically, we do two things. First, we present a new, third, set of spending numbers applying temporally consistent functional definitions to PESA microdata. Second, we compare the three measures. Our analyses indicate that the Office for National Statistics and PESA data differ quite markedly, especially for certain functions, i.e. in some cases the two measures imply completely different histories. The differences between the original PESA data and our new measures are less pronounced on average, though significant differences are evident, especially year by year.

SummaryThe paper investigates the effect on the wage distribution of the introduction, in April 1999, of the national minimum wage (NMW) in the UK. Because of the structure of UK earnings statistics, it is not straightforward to investigate this and various methods for adjusting the published statistics are discussed. The main conclusions are that the NMW does have a detectable effect on the wage distribution and that compliance with the NMW is widespread but the effect is limited because the NMW has been set at a level such that only 6–7% of workers are directly affected and the NMW has had virtually no effect on the pay of workers who are not directly affected. Furthermore, virtually all the changes occurred within 2 months of the introduction in April 1999 and its effect declined over time from April 1999 to September 2001 as the minimum wage was not uprated in line with the increase in average earnings. The more substantial increase in the NMW in October 2001 partially, but not wholly, restored some of this decline in impact.

To compensate for item nonresponse, hot deck imputation procedures replace missing values with values that occur in the sample. Fractional hot deck imputation replaces each missing observation with a set of imputed values and assigns a weight to each imputed value. Under the model in which observations in an imputation cell are independently and identically distributed, fractional hot deck imputation is shown to be an effective imputation procedure. A consistent replication variance estimation procedure for estimators computed with fractional imputation is suggested. Simulations show that fractional imputation and the suggested variance estimator are superior to multiple imputation estimators in general, and much superior to multiple imputation for estimating the variance of a domain mean.

SUMMARY Saddlepoint approximations are shown to be easy to use and accurate in a variety of simple bootstrap and randomization applications. Examples include mean estimation, ratio estimation, two-sample comparisons, and autoregressive estimation.