Stock Rollbar publishes a report after every trading day’s close — covering the Korean and US markets and the state of our systematic trading.
Why This Blog Exists
Korea is one of the world’s most dynamic markets, yet language and market-structure barriers keep many global investors away. Every report is published in both Korean and English: a structured market summary for Korean readers, and for global investors the context needed to make sense of this market — FX, flows, and the mechanics peculiar to Korea.
Who Writes This
Prunus mume — a fairly ordinary person in Korea, in my mid-thirties. I do not work in finance, I am not a licensed investment adviser, and I hold no certifications or institutional track record.
As an individual investor, in 2026 I made roughly what an average Korean salary pays from the market, and I aim to repeat that in 2027 and 2028. But that came from my own discretionary judgement. What this blog tests is the question that follows — take the human judgement out, and can rules alone do the same thing?
More on background and operating principles: Editorial & Data Policy.
How Stocks Are Picked
What I trust is not the shape of a chart but a company that actually makes money. Is revenue growing? Do operating margins hold up? Is cash genuinely coming in? Is the debt load survivable? A name that fails these drops out no matter how good its technical setup looks.
- Four consecutive profitable quarters — a hard requirement, verified against quarterly filings from DART (Korea) and SEC EDGAR (US).
- Missing data means excluded, not admitted — letting a name through when the check fails would mix in unverified companies.
- Technicals come second — trend and volatility only rank what already cleared the gate.
Fundamentals are the goal; the system is only how I find them — a tool for checking those conditions across hundreds of names every day, without tiring and without emotion.
That is why the stock reports here do not say “buy” or “sell.” They start from “how does this company make money?” I am learning as I write them, and the intent is that we look at the same things together.
Why Systematic
The starting point is a practical problem every individual investor has: can someone who cannot watch the market all day use a rules-based system to handle stock discovery, execution, and risk management automatically — spending far less time on the market without giving up performance?
We test that with an operating record rather than an argument. The system currently runs on a paper-trading account under real market conditions (live prices, realistic order execution), with a planned transition to real capital once it proves itself. Everything published here — watchlists, risk-gate calls, trading status — is the system’s actual record, published as it happens: wins, losses, and lessons alike.
What’s Inside, Daily
- Market snapshot — KOSPI, S&P 500, USD/KRW
- Large-cap movers & headlines — where money moved and what drove it
- Regime & risk diagnosis — Risk-On/Off call from volatility and FX, plus the state of the risk gates
- System watchlist — Korean and US names that cleared the fundamental gate and then ranked on technical score, plus the sectors in focus
- Stock deep dives — quarterly results, valuation, consensus, and how the company actually makes money
How Reports Are Made
Numbers, tables, and charts are computed by our own pipeline from public sources (Yahoo Finance, DART, SEC). The written sections are drafted by a large language model from those same numbers, under a rule never to invent figures absent from the data. We state this plainly rather than hiding it, and published reports are reviewed and corrected when something is wrong. Full detail: Editorial & Data Policy.
Disclaimer
Everything here is for information only and is not investment advice or a solicitation. All investment decisions and their outcomes are your own responsibility.