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When Scientists Go Wrong

first_imgScientific studies on scientists are not always encouraging.You probably shouldn’t rely on yesterday’s scientific guidelines about diet. The Guardian begins a critique of scientific consensus about nutrition with these words:In 1972, a British scientist sounded the alarm that sugar – and not fat – was the greatest danger to our health. But his findings were ridiculed and his reputation ruined. How did the world’s top nutrition scientists get it so wrong for so long?Flawed conclusions taught as fact for 40 years cannot be laid at the foot of corporations, Ian Leslie says. Nor does it show that scientists are open to new ideas as more evidence becomes available. Instead, this incident proves Planck’s maxim that science advances one funeral at a time. So how confident can we be about their advice today?At The Conversation, Jeremy Gibbons teases with the headline, “Science relies on computer modelling – so what happens when it goes wrong?” We don’t do science the old fashioned way, verifying the properties of nature by hands-on experiment. Gibbons, a professor of computing at Oxford, warns that computer models are simplifications of nature that cannot be precise:Modelling is used across scientific fields – ranging from astrophysics and climate prediction to bioinformatics and economics. But there is increasing debate about the fact that this science is difficult to validate through reproduction.It turns out that simply describing experimental methods in words is not enough. That’s partly because natural languages such as English are simply too vague for describing computations precisely. There is, after all, a reason why programmers use programming languages. One of the biggest challenges in software development is in converting vague requirements into precise specifications of behaviour.He points to clear cases of bugs in inputs and outputs. Often, results are not reproducible because other scientists may not understand what the authors did, what they meant, or even because of the way different programs handle the same numbers.Oh, but science is truth. Don’t be misled by facts! —Finagle.(Visited 22 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

South Africa takes note of ratings outlook

first_img8 June 2015Responding to Fitch Ratings’ latest rating assessment of South Africa, the government said it recognised that the country’s economic growth needed to be accelerated, and that it was addressing the issues raised by the international ratings agency at the highest level.Fitch affirmed South Africa’s long-term foreign and local currency Issuer Default Ratings at “BBB” and “BBB+” respectively, and also affirmed the negative outlook.It said key drivers for the rating decision included weak economic growth potential on the back of electricity supply constraints and external financing vulnerabilities. The country’s deep local markets enhanced fiscal financing flexibility, it added.The structure of government debt, 91% of which was denominated in local currency, limited exchange rate and refinancing risks. An improvement in the growth outlook and reduction in the current account and budget deficits would assist in stabilising the rating, Fitch said.In a statement issued by the National Treasury at the weekend, the government admitted that the country’s economic growth performance needed to be higher in order to address South Africa’s challenges. Resolving the energy challenge was a priority, it said.It pointed out that the government’s package to support Eskom was progressing, and that plans announced last week to allocate R23-billion into the company and convert a R60-billion loan into equity were firmly on track.“The implementation of priority reforms of the National Development Plan remains a key objective of [the] government. Growth enhancing initiatives and programmes, targeting key sectors of the economy such as the energy sector, are being implemented to support the country’s economic competitiveness,” said the National Treasury.It added that the government would broadly stick to its expenditure with regards to the fiscal position.Source: News24Wirelast_img read more