Long-memory models have been used by several authors to model data with persistent autocorrelations. The fractional and fractional autoregressive movingaverage (FARMA) models describe long-memory behavior associated with an in®nite peak in the spectrum at f 0. The Gegenbauer and Gegenbauer ARMA (GARMA) processes of Gray, Zhang and Woodward (On generalized fractional processes. J. Time Ser. Anal. 10 (1989), 233±57) can model long-term periodic behavior for any frequency 0 < f < 0X5. In this paper we introduce a k-factor extension of the Gegenbauer and GARMA models that allows for long-memory behavior to be associated with each of k frequencies in [0, 0X5]. We prove stationarity conditions for the k-factor model and discuss issues such as parameter estimation, model identi®cation, realization generation and forecasting. A two-factor GARMA model is then applied to the Mauna Loa atmospheric CO 2 data. It is shown that this model provides a reasonable ®t to the CO 2 data and produces excellent forecasts.

Using a panel of workplaces in Britain, we investigate the implications for businesses of employing older workers. Workplace labor productivity falls where the proportion of older or younger workers rises. These raw associations are attenuated somewhat after controlling for aspects of human capital. In contrast, there is no significant association between age shares and workplace financial performance, suggesting that any reluctance by employers to employ greater numbers of older workers may be misplaced.

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The articles published by the Annals of Eugenics (1925–1954) have been made available online as an historical archive intended for scholarly use. The work of eugenicists was often pervaded by prejudice against racial, ethnic and disabled groups. The online publication of this material for scholarly research purposes is not an endorsement of those views nor a promotion of eugenics in any way.

St Columba's Hospice, Edinburgh, is a busy specialist palliative care unit with 30 inpatient beds. A previous publication reported the first strand of a qualitative exploratory study evaluating the impact of open visiting on patients at the hospice. This paper reports on the second strand, which sought to elicit the views of the hospice staff through focus group interviews. The main themes identified were valuing the family and friends as visitors, involving the family as part of the care team, patient powerlessness over visiting, shared rooms and their impact on visitors and patients, and the staff role as advocates or gatekeepers. Several strategies for developing a flexible and 'patient-controlled' visiting policy were identified, including quiet times without visitors, restriction of visitor numbers in shared rooms, and encouraging breaks from visiting. Since the study was completed, the hospice's visiting policy has been modified to ensure that it is patient-centred and meets the needs of patients and families.