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Investigates the medical factors affecting the reliability of artificial heart valves using the proportional hazards model. The data, from a database which is still being assembled at Killingbeck Hospital, Leeds, refer to patients who have had artificial heart valves implanted. The analysis of the data has been carried out using a suite of programs not specifically designed with this application in mind. Illustrates the exploratory analysis, the parameter estimation for the model and the validation of the model, being a preliminary study to assess the value of the proportional hazards model for this area. Follow‐up work, as the database is revised and augmented, is intended.

Discusses the maintenance of n identical stations uni‐directionally patrolled by a maintenance operative. The time to travel between adjacent stations is a random variable and the time to repair a broken‐down station is also a random variable. Assumes that the breakdowns at each station occur randomly in running time and that only a proportion of attempted repairs is successful. Shows that all the important characteristics of the system – waiting time, response time, availability – depend on the probability, denoted by α, that a station is found in the failed state. Gives a procedure for computing this probability.

We recall Sidney Greenstreet's profile of Humphrey Bogart in The Maltese Falcon: ‘Upon my soul sir, you are a character, you really are.’ The same might be said of Gorby, the leader of the second most powerful country in the world, whose stated philosophy over seventy years has been: profit is a moral evil.

The inverse Gaussian distribution arises quite naturally as a model for failure times brought on by a “steady” deterioration in quality. If the underlying “wear” process is one of Brownian motion with a positive drift at rate µ, with variance σ2 per unit time, the first passage time T to a barrier at a distance a from the origin has p.d.f. of inverse Gaussian type.

Productivity in the UK has been improving over the last few years. A couple of small cheers are in order. However, much of the improvement has had little to do with the efforts of work study practitioners — it has been due more to the changes in government policy and changes in attitude of senior managers. Organisations have been slimmed down and made leaner and fitter. This applies across all industries and across the public/private sector divide. However, the changes we have seen have been largely one‐off exercises. If improvements are going to continue, we now need the systematic analysis and development of activities to be undertaken. But not in the old way!

MOST days, newspapers and TV tell us how yet more plants are closing down with a stated loss of jobs. There is another side to the picture that unfortunately is often lost in small paragraphs tucked away in a corner or to be found only in the columns of trade journals. They are the stories of the new factories opening, of new opportunities for those who are ready to seize them.

ACCORDING to a survey recently published salaries paid to administrative, professional and executive staff have lagged behind national wage increases when compared on a percentage basis. The actual figures, up to the end of January this year, show an increase of 13.1% against a national wage increase of 16.4%. So, concludes the report, “it is clear that traditional staff differentials are facing further erosion.” At the same time the opinion is expressed that once the current wage demands have been settled with the unions concerned, salaries for these higher grades will be rising at a rate of between 13% and 16%, probably by late summer.