安防股量化掘金：看懂行業紅利 用指標篩出穩健收益

The Visible Dividend from Urban Governance and AI

In recent years, artificial intelligence and fine-grained urban governance have frequently made headlines. From smart transportation to smart communities and emergency response, the demand for the “sensing layer” is expanding rapidly. Security is the core carrier of this sensing layer, and its industry dividend is often underestimated by many.

Is the security sector a good track for investment? The right answer is: it depends on how you select stocks.

Traditionally, the security industry relied heavily on project-based sales, meaning high receivables and fluctuating cash flow. That is why many investors have been hesitant. But today, with AI algorithms, edge computing, and cloud platforms gradually being deployed, security businesses are shifting from “selling hardware” to “selling services”. This shift directly leads to higher order visibility, healthier revenue structures, and more predictable cash flow.

For ordinary investors, instead of chasing hot headlines, it is smarter to use systematic metrics to perform quantitative stock selection and turn “feelings” into “logic.”

Quantitative Stock Selection: A Repeatable Method

Many people think “quantitative” means writing code or running complex models. In reality, quantitative stock selection for ordinary investors is not that complicated. The core is simply to use a clear set of indicators to filter out most unattractive stocks, then pick the best from the remaining candidates.

Let us take security stocks as an example and see how to use quantitative indicators to screen quality names.

Step 1: Look at P/E Ratio, but Not in Isolation

The price-to-earnings (P/E) ratio is the most commonly used valuation metric. However, a low P/E does not always mean cheap, and a high P/E does not necessarily mean expensive. In the security sector, you need to combine P/E with the industry average, the stock’s historical range, and expected earnings growth.

A practical approach: focus on stocks whose P/E ratio is below the 30th percentile of the industry, while forward two-year earnings expectations are positive. This helps avoid “fake cheapness” caused by deteriorating fundamentals, and at the same time captures valuation repair opportunities.

Step 2: Check the Persistence of Earnings Growth

Security industry orders are often seasonal, so single-quarter growth can be misleading. For ordinary investors, the TTM (trailing twelve months) net profit growth rate is a more reliable measure of the latest profitability trend. If a company has maintained positive TTM net profit growth for three consecutive quarters, it is a sign that order visibility and project execution are healthy.

Step 3: Follow Institutional Position Changes

Institutional money movement often reflects professional investors’ assessment of mid-to-long-term value. Public financial reports reveal how funds, insurers, QFII and other institutions adjust their holdings. If a security stock has been continuously added to by institutions for the past two quarters while the share price has not yet rallied sharply, the market may not have fully priced in the fundamental improvement.

Combining the above three conditions, you get a simple but effective quantitative screening framework:

• P/E ratio is below the industry median and earnings expectations are improving.
• TTM net profit growth is positive and above the industry average.
• Institutional holding ratios have increased for two consecutive quarters.

This is not a sophisticated algorithm, but it is enough to help you quickly narrow down the universe of over a hundred security-related companies, reducing the probability of stepping on landmines.

Quantitative Game Dynamics in HK, A-shares and US Markets

Security stocks exist on Hong Kong, A-shares and US markets, but the characteristics of these three markets differ significantly.

A-shares are more policy- and trend-driven. Theme speculation often dominates, leading to sharper price swings. Besides fundamentals, you need to account for policy-driven sentiment. Momentum strategies based on trend following can work in A-share security stocks, but you should be cautious about high-level volume stagnation.

Hong Kong places more emphasis on earnings quality and free cash flow. With more international investors, valuations are more aligned with global standards. Therefore, when investing in security stocks in Hong Kong, you should pay extra attention to net cash ratio and dividend payout ratio. Pure theme speculation rarely sustains; capital tends to reward companies with high ROE and stable cash flow.

In the US, the security market is mainly composed of technology-led and service-led companies. With institutional investors dominating the market, share prices adjust quickly to earnings expectation revisions. Consensus estimate changes can be a particularly useful quantitative factor here. Retail investors can also participate through ETFs, but should be aware of currency fluctuations and regulatory risks across borders.

Understanding these quantitative game dynamics across markets will help you tailor a strategy suitable for your capital size and risk appetite.

Avoiding the Top-Chasing Trap and Managing Capital

Many retail investors lose money in security stocks not because they picked the wrong company, but because they bought at the wrong price. This is especially true when industry sentiment heats up and the urge to chase rallies becomes strong.

Quantitative stock selection gives you a disciplined buying framework, not a promise of the next big winner. When the short-term price surge significantly exceeds earnings growth, even a great company should be patiently waited for or accumulated in tranches.

Here are three practical tips to avoid pitfalls:

1. Set a maximum position size: limit each security stock to no more than 20% of your total portfolio to prevent single-stock black swan damage.
2. Validate your holdings with earnings delivery: if a stock’s earnings growth misses expectations for two consecutive quarters, re-examine your thesis even if the share price has not dropped.
3. Review periodically, not daily: quantitative selection is a medium-term logic. Adjust every quarter to reduce transaction costs and emotional decisions.

Long-term Compounding: A Logic Any Ordinary Person Can Master

Investing is a marathon, not a sprint. The significance of quantitative stock selection is that it frees you from relying on insider tips or herd behaviour, allowing you to build your own decision-making system using public data.

Imagine this: you set aside a fixed amount every month to gradually buy a portfolio of security stocks that pass your screening criteria, and you review them each quarter. Even if the market fluctuates, as long as the industry trends upward, earnings growth of quality companies will eventually push the share price centre higher. The longer the time horizon, the more powerful the compounding effect.

Combining security stock investment with quantitative selection essentially transforms industry dividends into a repeatable source of income. Urban governance and AI adoption are still progressing, and the long-term demand for security solutions remains compelling. You do not need to be a programmer or possess institutional-grade databases. Simply mastering a few core metrics and keeping your emotions in check may be enough to share in the industry’s growth value.

Conclusion

From the AI urban governance boom to the transformation of security business models, the industry dividend is already on the table. But such dividends are not distributed equally to everyone.

Those who truly profit are often the ones with methods, discipline, and patience. Using quantitative indicators to pick quality security stocks is exactly the logic that ordinary people can grasp to build stable returns. May each of your decisions be backed by data, not clouded by emotions.