SOXL sinks ~38%, OpenAI's $1.25T raise, and the 0.1% fraud-model question

A chip rout pushed the Nasdaq into correction, OpenAI's valuation jumped to $1.25 trillion, and we walk through a staff-level fraud-model interview question. Markets: SOXL $45.97 (down roughly 35 to 40% on the week), VGT $108.51 (down about 7%), QQQ $656.10 (down about 6%), VUG $82.17 (down about 5%). AI news: Bloomberg reports OpenAI raised $11 billion at a $1.25 trillion valuation as Anthropic nears its IPO. Interview Tip of the Day: A fraud or abuse model has 0.1% positives. Why is accuracy meaningless, how do you pick the operating threshold from the cost of false positives versus misses, and how does adversary behavior break your validation set? Did You Know: Amazon began as an online bookstore in Jeff Bezos's garage, with a bell that rang for every order. Questions or feedback: [email protected]