2025-12-20 14:40:22

Here's something worth questioning about how we measure population trends. The total fertility rate model makes a pretty bold assumption: it treats young women's childbearing patterns as if they'll match not just their peers today, but also women who are five, even ten years older.

That's a stretch. Demographic patterns don't work in a vacuum. Economic cycles, policy shifts, access to resources—these all shift how generations actually behave over time. A woman's fertility rate at 25 isn't necessarily predictive of her rate at 35 just because some older cohort followed that pattern. Life happens between those years.

When we're building models for long-term trends—whether it's for economics, market cycles, or resource planning—these kinds of statistical shortcuts can compound into serious blind spots. Worth keeping in mind the next time you see demographic forecasts being used to argue anything about the future.

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BearMarketBarber

· 2025-12-23 13:41

You are absolutely right, this kind of linear predictive model is really absurd. According to this logic, my investment strategy at 25 can still be used at 35, how is that possible... The cycles, policy changes, and resource flows experienced in between are completely ignored, the model just automatically assumes you remain unchanged for 10 years.

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GateUser-6bc33122

· 2025-12-23 13:12

To be honest, this trap model is just a hard trap. Can the fertility rate of women at 25 predict that at 35? Anything can change in the ten years in between, such as the economy, policies, opportunities... doesn't any of this count?

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WenMoon

· 2025-12-23 07:21

It's absolutely ridiculous to use outdated data to trap today's women. When the economic situation changes, life plans have to be redone; how can models be copied over?

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ZeroRushCaptain

· 2025-12-21 20:35

This is a typical data model trap. The times I lost money in the crypto world came about this way. Directly applying past patterns to the future resulted in a 50% slump from reality. Demographers, like me, love to assume "history will repeat itself," and then get slapped in the face. When economic cycles, policies, and resources change, all predictions become worthless, and my buy the dip plan collapsed this way too. Using data from age 25 to predict age 35? Nonsense, ten years is enough to take a person from Full Position to close all positions. That's why every time I look at long-term predictions, I do the opposite and still end up dropping to zero, haha.

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RiddleMaster

· 2025-12-20 15:10

Basically, the models are just taking past data and applying it to the present. Real people are not that predictable. When economic policies change, the world becomes chaotic. TFR (Total Fertility Rate) can't really predict anything at all.

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MEVHunterZhang

· 2025-12-20 15:09

To be honest, this fertility rate model is just a rigid data fit... it completely doesn't consider how much can change in a decade of life.

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AirdropSkeptic

· 2025-12-20 15:07

This model is really outrageous. Using data from 5 or 10 years ago to predict the present? Wouldn't drastic changes in the economic situation and policies turn everything upside down?

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BrokenYield

· 2025-12-20 15:00

lol this is exactly the kind of model risk nobody talks about until it blows up. treating fertility like a static correlation matrix... nah, that's how you get black swan events in demographic forecasts tbh

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ServantOfSatoshi

· 2025-12-20 14:54

To be honest, the population model has long needed to be reconsidered. Simply applying historical data to predict the future has too many logical flaws... Economic conditions, policies, and resource availability are all changing. Why assume that a 25-year-old's fertility rate can predict that of a 35-year-old? In ten years, there will be earth-shaking changes.

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