--- title: "AI Stock Chat, 2026-09-21: Taiwan stocks lean bullish before Tuesday's open, though the hit rate is honestly not great." description: "Hello everyone, welcome to \"AI Stock Chat,\" I'm Muyan. Today is Monday, September 21, 2026, the domestic market is closed, so this episode we'll be looking at the next trading day, Tuesday, September 22. The AI model's call this time leans bullish, but hold on for the accuracy numbers, honestly the recent predictions haven't been very accurate, and we'll lay out all the figures for you." canonical_url: "https://blog.markkulab.net/en/ai-stock-chat/ai-stock-chat-2026-09-21" author: "Mark Ku" author_url: "https://blog.markkulab.net/en/author/mark-ku" site: "Mark Ku's Tech Notes" date_published: "2026-09-21 10:00:00 +0800" category: "AI Stock Chat" tags: ["ai-stock", "podcast", "台股預測", "台股", "AI預測", "瑞昱", "中信金", "華碩", "中華電", "陽明"] language: "en" license: "CC BY 4.0" license_url: "https://creativecommons.org/licenses/by/4.0/" attribution: "when reusing or quoting, credit the author and link back to the original" --- # AI Stock Chat, 2026-09-21: Taiwan stocks lean bullish before Tuesday's open, though the hit rate is honestly not great. > **TL;DR** — Taiwan's Weighted Index AI forecast for Tuesday, September 22 leans bullish with 54% confidence in a 46419.21，46944. ## Opening Hi everyone, welcome to AI Stock Chat, I'm Muyan. Today is Monday, September 21, 2026, and the domestic market is closed, so in this episode we're looking ahead to the next trading day, Tuesday, September 22. The AI model's call this time leans bullish, but when we get to the hit rate section later, I'll be honest with you, our recent calls haven't been very accurate, and we'll lay out all the numbers for you as a reference. ## Today's Market Forecast
Current 47180.75Next dayBullish · 46419.21~46944.07 · Confidence 54%Short-termBullish · 46581.40~47755.02 · Confidence 54%
Weighted Index AI Forecast Range (Next Day / Short-term)
| Horizon | Current Price | Forecast Direction | Target Range | Confidence | | --- | --- | --- | --- | --- | | Next day | 47180.75 | Bullish | 46419.21~46944.07 | 54.0% | | Short-term | 47180.75 | Bullish | 46581.4~47755.02 | 54.0% | Looking at the market interpretation report, sentiment is indeed leaning bullish, with advancing stocks far outnumbering decliners and a strong bullish mood overall. That said, a 54% confidence level really only counts as a "slight" bullish lean, not an overwhelming, strong signal. Treat this target range as a reference only, don't go all-in just because the call is bullish. ## Global Market Overview | Index | Close | Change % | | --- | --- | --- | | Taiwan Futures Night Session (TXF) | 47405 | -0.05% | | Dow Jones Industrial Average (DJI) | 51682.64 | -0.18% | | S&P 500 (GSPC) | 7650.5 | 0.17% | | Nasdaq Composite (IXIC) | 26522.55 | 0.39% | | Philadelphia Semiconductor Index (SOX) | 11921.69 | 2.78% | The Taiwan Futures night session dipped a slight 0.05%, essentially flat. The four major US indices were mixed but none moved by much, though the Philadelphia Semiconductor Index's 2.78% gain really stood out, which should offer some psychological support for Taiwan's tech stocks. ## Strategy Stock Radar The following are strategy screening results, not buy/sell recommendations for individual stocks. | Stock | Composite Score | Capital Flow Score | P/E Ratio | Valuation | | --- | --- | --- | --- | --- | | Realtek (2379) | 74 | 100 | , | , | | CTBC Financial (2891) | 71 | 100 | 16.63 | expensive | | ASUS (2357) | 70 | 100 | 14.04 | fair | | Chunghwa Telecom (2412) | 69 | 100 | 28.59 | expensive | | Yang Ming Marine Transport (2609) | 69 | 100 | , | , | On the technical side, Realtek is showing signs of stabilizing, and CTBC Financial's trading volume has picked up noticeably. Each of these stocks has its own tug-of-war between bullish and bearish signals. Chunghwa Telecom, for example, is popular right now, but both its RSI and Williams %R are flashing overbought warnings, a reminder to check the capital flow and valuation metrics yourself before making any calls. ## Recent Forecast Hit Rate Review
Index · Next day29% (2/7)Index · Short-term33% (1/3)
Recent Directional Hit Rate (higher = more accurate; includes settled sample count)
Honestly, the recent hit rate for the index's next-day direction is only 28.6%, we got it right just 2 out of 7 times, and the range prediction went 0 for 7. Stretching out to the week-long short-term view, the hit rate is 33.3%, correct 1 out of 3 times, though the range prediction did land once out of three. Average error runs about 0.73% for next-day and about 2.47% for short-term. Accuracy over this stretch really hasn't been great, which is exactly why we insist on laying all the numbers out for you every episode. Please treat this strictly as a reference, investment decisions and risk management are still up to you. ## Disclaimer This content is automatically generated by an AI model based on quantitative data. It is provided for research reference only and does not constitute investment advice or a recommendation of any kind. This site and the program's producers are not a licensed securities investment advisory business, do not provide analysis opinions to any specific individual, and receive no compensation of any kind for this content. Investing involves risk; please make your own judgments and bear your own responsibility. --- ## About this article and its author Originally published on [Mark Ku's Tech Notes](https://blog.markkulab.net/en/ai-stock-chat/ai-stock-chat-2026-09-21) License: [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/) — when reusing or quoting, credit the author and link back to the original ### About the author **[Mark Ku](https://blog.markkulab.net/en/author/mark-ku)** — 226 Network Co. · Software engineer - 10+ years as a software engineer, now running 226 Network - Built North-American e-commerce and AI SaaS subscription billing - Systems, websites, LINE bots and AI automation for small companies ### Free tools built by the author All of these are free to use: - [Free PDF Sign Tool](https://blog.markkulab.net/en/tools/pdf-sign): Online PDF sign tool — draw, type, or upload a signature, then drag, resize, and download. 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