You don’t always save money by putting your investments into a 401(k).

When you invest money inside a 401(k), you don’t have to pay taxes on any returns earned by your investments. But you also have to pay a fee to your 401(k) provider.

• If you buy and hold index funds in a taxable account, you don’t have to pay any capital gains tax on price increases until you sell.
• In a 401(k), the annual fee adds up every year and may eventually exceed the tax savings.

So the taxes cap out at the capital gains tax rate (15% or 20% depending on your tax bracket),¹ whereas the expenses of a 401(k) continue to accumulate.

However, in a taxable account, you do still have to pay taxes on dividends (and bond payouts) every year, and those taxes might cost you more than the 401(k) fees.²

Below is a calculator to determine how many years before the 401(k) fees exceed the tax savings, if ever.

employer matching (%)
total investment return including dividends (nominal) (%)
dividend yield (%)
401(k) fee (%)
capital gains tax rate (%)
income tax rate today (%)
income tax rate in retirement (%)

A 401(k) falls behind a taxable account after:

This calculator assumes you buy index funds and hold them forever. If you trade stocks within a taxable account, you have to pay taxes every time you make a trade.

Something else to consider: If you quit your job, your old employer’s 401(k) provider will let you roll your 401(k) into an IRA. You don’t have to pay any fees on an IRA.³ So even if the 401(k) fees exceed the tax benefits after (say) 30 years, that’s not a problem if you expect to quit your job after less than 30 years. Realistically, few people stay at one job for so long that the 401(k) fees exceed the tax savings.

(If you change jobs, usually you can roll your old 401(k) into your new 401(k), but I wouldn’t do that because it means you have to keep paying 401(k) fees. It’s almost always better to roll your old 401(k) into an IRA.)

Notes

I did another caffeine experiment on myself. This time I tested if I could have caffeine 4 days a week without getting habituated.

Last time, when I took caffeine 3 days a week, I didn’t get habituated but the results were weird. This time, with the more frequent dose, I still didn’t get habituated, and the results were weird again!

Continue reading

Last time, I found that the healthiest BMI range for all-cause mortality is 20–22. But BMI doesn’t tell the whole story. Most obviously, it doesn’t account for body fat vs. lean mass. All else equal, you’d rather have more muscle¹ and less fat.

So what’s the healthiest combination of lean mass + fat mass?

I’m not going to answer that question because I can’t. Instead, I will explain why I can’t, and then give a rough guess at the answer.

Scientists have been measuring and collecting data on BMI for decades. You can find plenty of giant BMI studies with three million participants in various countries.

We have much sparser data on body fat. Scientists didn’t start collecting data on body fat until the last few decades. And body fat is harder to measure—we have various methods for estimating body fat, but they’re all more complicated than calculating BMI.

I managed to scrounge together some studies on body fat and mortality. My best guess: the average woman should aim for a BMI of 21 with 20% body fat, and the average man a BMI of 21 with 10% body fat. (Subject to individual variation due to genetics and whatnot.)

Trans men should probably target the same body fat % as cis men, and likewise for trans women and cis women, because hormone therapy alters body fat distribution (Spanos et al. (2020)²).

The evidence weakly suggests that there is no lower bound on healthy fat mass, and no upper bound on healthy lean mass. We have so little mortality data on extremely lean + muscular people that we can’t say how healthy they are.

A more in-depth analysis would look at a variety of health indicators (blood pressure, HDL cholesterol, etc.) and use that to predict mortality. I didn’t do that, I just looked at mortality data.

Continue reading

TLDR: 20 to 22.

Continue reading

Last updated 2024-07-26 to clarify wording.

Confidence: Likely.

I conducted an experiment on myself to see if I would develop a tolerance to caffeine from taking it three days a week. The results suggest that I didn’t. Caffeine had just as big an effect at the end of my four-week trial as it did at the beginning.

This outcome is statistically significant (p = 0.016), but the data show a weird pattern: caffeine’s effectiveness went up over time instead of staying flat. I don’t know how to explain that, which makes me suspicious of the experiment’s findings.

Continue reading

Confidence: Likely.

If you take caffeine every day, does it stop working? If it keeps working, how much of its effect does it retain?

There are many studies on this question, but most of them have severe methodological limitations. I read all the good studies (on humans) I could find. Here’s my interpretation of the literature:

• Caffeine almost certainly loses some but not all of its effect when you take it every day.
• In expectation, caffeine retains 1/2 of its benefit, but this figure has a wide credence interval.
• The studies on cognitive benefits all have some methodological issues so they might not generalize.
• There are two studies on exercise benefits with strong methodology, but they have small sample sizes.

Continue reading

Summary

Caffeine improves cognition¹ and exercise performance². But if you take caffeine every day, over time it becomes less effective.

What if instead of taking caffeine every day, you only take it intermittently—say, once every 3 days? How often can most people take caffeine without developing a tolerance?

The scientific literature on this question is sparse. Here’s what I found:

1. Experiments on rats found that rats who took caffeine every other day did not develop a tolerance. There are no experiments on humans. There are no experiments that use other intermittent dosing frequencies (such as once every 3 days).

2. Internet forum users report that they can take caffeine on average once every 3 days without developing a tolerance. But there’s a lot of variation between individuals.

This post will cover:

1. The motivation for intermittent dosing

2. A review of the experimental research on the effect of taking caffeine intermittently (TLDR: there’s almost no experimental research)

3. A review of self-reports from the online nootropics community

4. Intermittent dosing vs. taking caffeine every day

Continue reading

TLDR: No.

Confidence: Somewhat likely.

Summary

Some philanthropists discount the future much less than normal people. For philanthropists with low discount rates, does this change how they invest their money? Can they do anything to take advantage of other investors’ high time discounting?

We can answer this question in two different ways.

Should low-discount philanthropists invest differently in theory? No. [More]

Should low-discount philanthropists invest differently in practice? The real world differs from the standard theoretical approach in a few ways. These differences suggest that low-discount philanthropists should favor risky and illiquid investments slightly more than high-discount investors do. But the difference is too small to matter in practice. [More]

Continue reading

Summary

Confidence: Likely. [More]

Some people have asked, “should we invest in companies that are likely to do particularly well if transformative AI is developed sooner than expected?”¹

In a previous essay, I developed a framework to evaluate mission-correlated investing. Today, I’m going to apply that framework to the cause of AI alignment.

(I’m specifically looking at whether to mission hedge AI, not whether to invest in AI in general. [More])

Whether to mission hedge crucially depends on three questions:

1. What is the shape of the utility function with respect to AI progress?
2. How volatile is AI progress?
3. What investment has the strongest correlation to AI progress, and how strong is that correlation?

I came up with these answers:

1. Utility function: No clear answer, but I primarily used a utility function with a linear relationship between AI progress and the marginal utility of money. I also looked at a different function where AI timelines determine how long our wealth gets to compound. [More]
2. Volatility: I looked at three proxies for AI progress—industry revenue, ML benchmark performance, and AI timeline forecasts. These proxies suggest that the standard deviation of AI progress falls somewhere between 4% and 20%. [More]
3. Correlation: A naively-constructed hedge portfolio would have a correlation of 0.3 at best. A bespoke hedge (such as an “AI progress swap”) would probably be too expensive. An intelligently-constructed portfolio might work better, but I don’t know how much better. [More]

Across the range of assumptions I tested, mission hedging usually—but not always—looked worse on the margin² than investing in the mean-variance optimal portfolio with leverage. Mission hedging looks better if the hedge asset is particularly volatile and has a particularly strong correlation to AI progress, and if we make conservative assumptions for the performance of the the mean-variance optimal portfolio. [More]

The most obvious changes to my model argue against mission hedging. [More] But there’s room to argue in favor. [More]

Continue reading

Summary

TLDR: According to my preliminary model, the altruistic investing portfolio should ultimately allocate 5–20% on a risk-adjusted basis to mission-correlated investing. But for the current EA portfolio, it’s better on the margin to increase its risk-adjusted return than to introduce mission-correlated investments.

Last updated 2022-04-06.

The purpose of mission-correlated investing is to earn more money in worlds where your money matters more. For instance, if you’re working to prevent climate change, you could buy stock in oil companies. In worlds where oil companies are more successful and climate change gets worse, you make more money.

Previous work by Roth Tran (2019)¹ proved that, under certain weak assumptions, philanthropists should invest more in so-called “evil” companies than they would from a pure profit-making standpoint. This result follows from the assumption that a philanthropist’s actions become more cost-effective when the world gets worse along some dimension.

That’s an interesting result. But all it says is altruists should invest more than zero in mission hedging. How much more? Am I supposed to allocate 1% of my wealth to mission-correlated assets? 5%? 100%?

To answer this question, I extended the standard portfolio choice problem to allow for mission-correlated investing. This model makes the same assumptions as the standard problem—asset prices follow lognormal distributions, people experience constant relative risk aversion, etc.—plus the assumption that utility of money increases linearly with the quantity of the mission target, e.g., because the more CO2 there is in the atmosphere, the cheaper it is to extract.

I used this model to find some preliminary results. Future work should further explore the model setup and the relevant empirical questions, which I discuss further in the future work section.

Here are the answers the model gives, with my all-things-considered confidence in each:

• Given no constraints, philanthropists should allocate somewhere between 2% and 40% to mission hedging on a risk-adjusted basis,² depending on what assumptions we make. Confidence: Somewhat likely. [More]
• Given no constraints, and using my best-guess input parameters:
  • Under this model, a philanthropist who wants to hedge a predictable outcome, such as CO2 emissions, should allocate ~5% (risk-adjusted) to mission hedging.
  • Under this model, a philanthropist who wants to hedge a more volatile outcome, for example AI progress, should allocate ~20% to mission hedging on a risk-adjusted basis.
• If you can’t use leverage, then you shouldn’t mission hedge unless mission hedging looks especially compelling. Confidence: Likely. [More]
• If you currently invest most of your money in a legacy investment that you’d like to reduce your exposure to, then it’s more important on the margin to seek high expected return than to mission hedge. Confidence: Likely. [More]
• The optimal allocation to mission hedging is proportional to: (Confidence: Likely)
  1. the correlation between the hedge and the mission target being hedged;
  2. the standard deviation of the mission target;
  3. your degree of risk tolerance;
  4. the inverse of the standard deviation of the hedge.

Cross-posted to the Effective Altruism Forum.

Continue reading