The mental block

Estimates of rates of stalking vary considerably, with 12 to 32 per cent of women reporting it having happened to them, and 4 to 17 per cent of men. To obtain more rigorous figures, a sample of 679 Germans were surveyed (British Journal of Psychiatry). Twelve per cent had suffered the problem, seven times more of them being women than men. Three-quarters of the stalkers were known to the victim - 32 per cent were rejected ex-lovers, 20 per cent a friend/acquaintance, 9 per cent a colleague. The most common pestilential behaviour was unwanted telephone calls (78 per cent), then dodgy loitering (63 per cent) and undesired letters, emails or faxes (50 per cent). In 42 per cent of cases, sexual harassment occurred, and physical assault happened in 31 per cent. A quarter of the victims sought professional help, with anxiety (44 per cent) and depression (28 per cent) as prominent symptoms. Implication: stalking is both common and has lasting ill-effects.

Does hot weather increase the likelihood of violence? Uncomfortably high temperatures definitely have a negative effect. Some studies suggest that once it gets beyond a certain temperature (around 90C) people are too soporific to get annoyed. However, they fail to take into account the time of day, which is crucial, because most violence happens between 9pm and 2am. A study in Minneapolis (Journal of Personality and Social Psychology) shows that even extreme heat does not cut violence in the evening. Implication: learn self-defence before global warming gets any worse.