Tag Archives: kids

Carly’s Law

Fifteen-year-old South Australian Carly Ryan was murdered in 2007. The 50-year-old man found guilty of her murder had used fabricated online identities to attempt to seduce the girl and, when she ultimately rejected his advances, he used another identity to lure her to a beach-side town where he bashed and drowned her.

Independent South Australian senator Nick Xenophon now intends to introduce a private member’s bill which would make it an offence for an adult to misrepresent their age online for the purpose of meeting minors. Carly’s mother, who plans to establish a foundation to promote awareness of the risks children face online, has said she supports the bill.

The story of Carly Ryan is terrible. Just hearing the story triggers a shiver of disgust and horror and those who are parents themselves may well be worrying about the risks posed to their own children by shadowy online stalkers. Politicians are human too and react the same way. Indeed Nick Xenophon’s reaction follows a common pattern that has emerged around the world in recent decades.

The pattern starts with a terrible crime committed against a child. This is followed by extensive and sometimes lurid media coverage. A politician will then call for new laws to “prevent this happening to others”. It would be a brave politician who would argue against such a law and thereby risk appearing insensitive to the plight of the victim and the grief of their distraught family. So they do not oppose it and new laws are passed. The pattern is clearest in the United States. The archetypal example is Megan’s Law. In 1994 seven-year-old Megan Kanka was raped and murdered by a repeat sexual offender. Her name has since been attached to laws introduced across the country requiring a public register of sex offenders. Other examples fitting the pattern include Jessica’s Law in Florida which imposes a minimum 25-year sentence on sex offenders. Nick Xenophon’s “Carly’s Law” could well be another in this sequence.

But, how effective are laws like this in curbing the criminal behaviour they are targeting? Continue reading

The Mathematics of NT-plus Screening

Update: regular commenter Mark L has helpfully identified they reason behind the apparent anomaly in the statistics that motivated me to write this post. I had misinterpreted one of the statistics. While this takes the mystery out of the numbers, it does highlight how tricky it can be to get to grips with the statistics of medical tests. I have edited this post to correct that misinterpretation. I decided not to use a the strikethough editing approach popular among bloggers as the content can be confusing enough already!

Despite the fact that more banks have been failing (Bradford & Bingley, Wachovia, Hypo Real Estate, Fortis,…), in this post I will continue to stay away from the subject of the financial markets and will instead look at some mathematics, trying not to lose too many readers in the process.

Recently I was contemplating results from an “NT-plus” test, which combines ultrasound measurements of the nuchal translucency with maternal blood-tests to provide a screening test for various chromosomal abnormalities, particularly Down Syndrome. Tests of this type abound with statistics and the mathematician in me could not resist crunching the numbers a little to get a better understanding of the test.

Continue reading

2042: Art on the Street

It’s time for a break from watching the financial markets implode. Instead, this post will focus on the arts, Newtown-style. Every year, the shops of Newtown become an extended gallery exhibiting the works of young Australian artists. Or at least, that’s how I describe it. According to the City of Sydney website, the aim of the exercise is “to combat the exclusivity fostered by institutional gallery spaces”. In years gone by, the exhibition was called “Walking the Streets”, but this year it goes by the name “2042: Art on the Street”. For those who are not local, 2042 is the postcode of Newtown and the immediate surrounds.

Being locals, Henry, my five year-old son, and I took a walk up King Street today to look at some of the works on show. Inspired by the blog Nosey in Newtown, we decided we would document the event, so we set off both armed with cameras. The undoubted favourite was the sculpture of giant ants beginning to rip into a car.

Continue reading