Vietnam deleted the rule that made its ID numbers decodable, and nobody stopped decoding them
Since 1 July 2024 no Vietnamese instrument says the 12-digit citizen ID has any internal structure. The decree defining...
Guides & How-tos · Worked examples · Real numbers
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One embedding model, four different maximum lengths
The most downloaded sentence-embedding model ships four config files declaring 128, 256, 512 and 512 as its maximum input length. Which one binds depends on your import statement, nothing warns you, and text past the cut is discarded silently — so two chunks differing only in a late sentence embed to almost the same vector.
Published 5 Sep 2026
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The annual Sharpe ratio hides an assumption about your returns
Annualising a monthly Sharpe ratio by multiplying by the square root of twelve is not a unit conversion. It is Andrew Lo...
One sky, three verdicts: why Singapore says unhealthy and Malaysia says moderate
The same 70 micrograms of fine particulate reads 116 on Singapore's PSI, 96 on Malaysia's API and 161 on the US AQI. Alm...
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Malaysia banned the Rule of 78, and the Rule of 78 was never the expensive part
On Bank Negara's own worked example the Rule of 78 costs an early settler at most about RM632 on a RM100,000 loan. Readi...
The DMARC tag that meant 10% of the time now means all the time
RFC 9989 removed the pct tag in May 2026, and the same document says receivers must ignore tags that are not registered....
Singapore's 3 days and Malaysia's 72 hours are not the same deadline
Both look like the same breach-notification window, but the clocks start at different events. Singapore's three days beg...
A distress-zone Z-score does not mean a 70% chance of bankruptcy
The Altman Z-score's famous 70% is the share of firms that DID fail which had scored in the distress zone — a sensitivit...
Four ASEAN countries have no time zone of their own
Asia/Phnom_Penh, Asia/Vientiane, Asia/Kuala_Lumpur and Asia/Brunei are not time zones. They are links, and the files beh...
New air conditioners clear a global-warming limit on 2013 figures
Singapore bars household air conditioners whose refrigerant exceeds a global warming potential of 750. The regulator pub...
The calcium formula everyone uses is not the one it cites
Corrected calcium is computed with a coefficient of 0.8 and attributed to Payne 1973 on virtually every clinical referen...
The Army stopped taping. The Marines did not.
Both services replaced the tape test with waist-to-height ratio in 2026 and then disagreed twice over. The Army set the...
Half the pronunciation changes people argued about had already happened
The viral lists of Chinese readings the ministry supposedly changed trace to a 2016 draft that was never issued. But the...
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