Staged Portfolio Allocation and the Limits of Dollar-Cost Averaging
Summary
The document asks how to deploy a fixed cash allocation into an asset class while seeking a favorable average purchase price. Its example splits an allocation into several buys at progressively lower index levels, then contrasts that idealized path with markets that rebound early or continue falling. These paths show the tradeoff between holding cash for lower prices and missing gains when prices rise before later purchases occur.
The answer argues that investors need to decide whether market conditions justify buying, waiting, or using hedges such as index futures or put options. It criticizes dollar-cost averaging and favors buying strength and selling weakness, but supports these claims with personal opinion and anecdotal experience rather than comparative evidence. The document offers no formal execution schedule, optimization framework, or risk-adjusted test, so its directional advice should not be treated as a demonstrated universal rule.
Key ideas
- Splitting a cash allocation into staged purchases can produce different outcomes depending on the subsequent price path.
- Waiting for lower prices preserves cash but can leave an investor underinvested after a rebound.
- The answer frames allocation timing as a choice among buying, waiting, and hedging exposure.
- Its criticism of dollar-cost averaging and preference for buying strength are opinions without systematic evidence in the document.
Tags
Full text
# Methods for distributing cash into allocation
# Methods for distributing cash into allocation
Are there any methods/techniques that cover distributing cash into a specific percent of a portfolio asset class while gaining the best average price?
As a simple example, a portfolio starts with 100k cash. It eventually disburses its cash into four asset classes. This means 25k goes to purchase assets in each class. If one of these classes is the SP500 index, you might decide to divide the 25k into four purchases, getting a better price with each purchase. For example, assuming the SP500 is dropping, purchase might be made at:
```
$6250 buy 1350
$6250 buy 1325
$6250 buy 1300
$6250 buy 1275
```
For an average price of 1312.50 in your SP500 allocation of the portfolio. However, in the real world, you will not be so lucky. You might buy 1350, the SP500 drops to 1339, then bounces to 1362 and remains above 1350 for the next few weeks. You only made one purchase and was not able to take better advantage of gains in the SP500. Or, it may continue dropping to 1225. You spent all your 25% allocation for this class at 1275 and are not able to take advantage of a much better average price.
Funds are available upfront. Shorting isn't allowed.
What area covers techniques that deal with this topic?
## Answer by Matt Wolf (score 3, accepted)
https://quant.stackexchange.com/a/3761
Even if some buy side funds are not allowed to short sell it does not mean they must buy. They could long sell, they can do nothing and stand on the sidelines and they can hedge, selling index futures or buy put protection on broad indexes or on the underlying of core holdings. Why this is an important point becomes apparent when you start to think about your question.
You are basically asking what a fund should do when it thinks prices go down and what a fund should do when it thinks prices go up. You may disagree but in the end this is what every fund, every trader, portfolio manager has to ask him/herself. Most of the times when market move in your favor you will not be as fully invested as you wished and often times markets simply trade against your position. Dollar cost averaging is one of the worst investment techniques and lead to the poor house, long term, no matter what some academic papers have to say. Its simply stupid to bet against the market. If you believe markets will ease and you cannot short then simply do nothing or buy protection but DONT BUY. So, I am not sure what further guidance beyond what I mentioned you really look at.
It's funny but academicians love to make things very complex and complicated, maybe because they are partly forced to do so by remaining generic in their research. However, trading and investing has not much to do with complexity. In the end it is very simple math and a very keen interest in human psychology that made a very small group of traders incredibly rich over time. I do not know of a whole lot of quant desks which did not blow up in a 10 year period. I know only less than 10 very successful traders personally in my 13 years in this industry who scored consistent but high returns at very manageable draw downs and return volatility.
So, my friend I think you are asking the right question but in the completely incorrect context. There is a reason that most "long-only" (sorry Chris ;-) traditional buy-side guys have very little to show for, one big reason being that successful hedge fun managers buy into strength and sell into weakness, while a lot of traditional buy side guys love to play their dollar cost averaging game and believe cheap stocks are not cheap for a reason.Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.