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The inverse problem for Earth structure from normal mode data is strongly non-linear and can be inherently non-unique. Traditionally, the inversion is linearized by taking partial derivatives of the complex spectra with respect to the model parameters (i.e. structure coefficients), and solved in an iterative fashion. This method requires that the earthquake source model is known. However, the release of energy in large earthquakes used for the analysis of Earth's normal modes is not simple. A point source approximation is often inadequate, and a more complete account of energy release at the source is required. In addition, many earthquakes are required for the solution to be insensitive to the initial constraints and regularization. In contrast to an iterative approach, the autoregressive linear inversion technique conveniently avoids the need for earthquake source parameters, but it also requires a number of events to achieve full convergence when a single event does not excite all singlets well. To build on previous improvements, we develop a technique to estimate structure coefficients (and consequently, the splitting functions) using a derivative-free parameter search, known as neighbourhood algorithm (NA). We implement an efficient forward method derived using the autoregresssion of receiver strips, and this allows us to search over a multiplicity of structure coefficients in a relatively short time. After demonstrating feasibility of the use of NA in synthetic cases, we apply it to observations of the inner core sensitive mode 13S2. The splitting function of this mode is dominated by spherical harmonic degree 2 axisymmetric structure and is consistent with the results obtained from the autoregressive linear inversion. The sensitivity analysis of multiple events confirms the importance of the Bolivia, 1994 earthquake. When this event is used in the analysis, as little as two events are sufficient to constrain the splitting functions of 13S2 mode. Apart from no

The Referral Order The Youth Justice and Criminal Evidence Act 1999 introduces a new primary sentencing disposal - the referral order - for 10-17 year olds pleading guilty and convicted for the first time by the courts. The disposal involves referring the young offender to a youth offender panel (YPO). The work of YOPs is to be governed by the principles 'underlying the concept of restorative justice': defined as 'restoration, reintegration and responsibility' (Home Office 1997, 31-32). The Pilots Referral orders are currently being piloted in eleven areas: Blackburn with Darwen, Cardiff, Nottingham, Nottinghamshire, Oxfordshire, Swindon, Suffolk, Wiltshire, Hammersmith and Fulham, Kensington and Chelsea, and Westminster. The introduction of referral orders was staggered across the pilot areas over the summer 2000. It is intended that national roll-out of referral orders will being in 2002. This report This report concentrates on the first phase of pilots covering the period of staff and community panel member recruitment, the first training programme, the views of the Youth Court clerks and magistrates and the initial experiences emerging from the panels. Published as Home Office Research and Development Statistics Division Occasional Paper No. 70