The logical fallacy behind "Bonds Are For Safety"

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Call_Me_Op
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Call_Me_Op » Tue Jun 11, 2019 7:02 am

You are over-thinking this.
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vineviz
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 8:14 am

Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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305pelusa
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by 305pelusa » Tue Jun 11, 2019 8:23 am

vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 8:29 am

305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
First, I'm admittedly showing my annoyance at the use of ad hominem arguments and semantic quibbles as a means of avoiding discussion around the actual points I raised in the OP.

Second, the use of sarcasm and/or hyperbole isn't the same as committing a straw man fallacy.

Third, can you provide an interpretation of "you are over-thinking this" that can't be reasonably interpreted as an appeal to anti-intellectualism?
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by JoMoney » Tue Jun 11, 2019 8:31 am

"Neither irony nor sarcasm is argument"
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Dialectical Investor » Tue Jun 11, 2019 8:32 am

This is a good thread with a lot to unpack, but as I re-read some posts, what I thought was a thread about the very proper advice to consider the behavior of the portfolio as a whole rather than focusing on its individual parts, seems at times to devolve into a simple refrain of advising the use of long-term bonds for investors with a "long time horizon." But if the original spirit of this thread prevails, that would not be the main takeaway, and it does contradict the original premise of assessing the portfolio as a whole.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by JoMoney » Tue Jun 11, 2019 8:41 am

Dialectical Investor wrote:
Tue Jun 11, 2019 8:32 am
This is a good thread with a lot to unpack, but as I re-read some posts, what I thought was a thread about the very proper advice to consider the behavior of the portfolio as a whole rather than focusing on its individual parts, seems at times to devolve into a simple refrain of advising the use of long-term bonds for investors with a "long time horizon." But if the original spirit of this thread prevails, that would not be the main takeaway, and it does contradict the original premise of assessing the portfolio as a whole.
... I disagree. It's a lousy thread that appears to be just be someone arguing why they believe in MPT/MVO portfolios, railing against what they imagine someone else means by the word "safety", and loosely arguing they like long-term bonds without ever really saying so. I suspect because (like most any MVO portfolio) any specific recommendation would be time period sensitive, of dubious past results, and unknowable future results. The argument would have to be narrowed to a specific claim rather than waxing on about what they think other people should think or arguing over the definition of words for the sake of an argument.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by sschullo » Tue Jun 11, 2019 8:42 am

For years, the pundits have been saying that bonds are going to crash when interest rates increase.
Interest rates have increased and my VG total bond market index had gone down to as low as $10.30 something.
Yesterday, VG TBM NAV was $10.85 after yesterday's close. 2.5 years ago before interest rates started to rise, it was priced at $10.99.

This great bond fund is doing exactly what I want it to do, calm the equity allocation of my portfolio.
Public School K-12 Educators: "Ask NOT what your annuity sales person can do for you, ask what you can do to be a Do-It-Yourselfer (DIY)."

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Call_Me_Op » Tue Jun 11, 2019 8:43 am

vineviz wrote:
Tue Jun 11, 2019 8:29 am
305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
First, I'm admittedly showing my annoyance at the use of ad hominem arguments and semantic quibbles as a means of avoiding discussion around the actual points I raised in the OP.

Second, the use of sarcasm and/or hyperbole isn't the same as committing a straw man fallacy.

Third, can you provide an interpretation of "you are over-thinking this" that can't be reasonably interpreted as an appeal to anti-intellectualism?
Adding (high-quality) bonds to a portfolio increases its safety. This may not sound like a particularly sophisticated statement - but it is correct. We can get into all kinds of arguments about advantages of longer duration bonds under certain circumstances, but the statement "bonds are for safety" is intended to keep things simple and to remind us of why we should include bonds in our portfolios.

I think we tend to do the same type of "over-thinking" across the board when it comes to investing. I am guilty of it sometimes as well. But when we study the history, our returns and risk (volatility) basically derive from our stock/bond mix. Doesn't give us much to talk about though.
Best regards, -Op | | "In the middle of difficulty lies opportunity." Einstein

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Dialectical Investor » Tue Jun 11, 2019 8:51 am

JoMoney wrote:
Tue Jun 11, 2019 8:41 am
Dialectical Investor wrote:
Tue Jun 11, 2019 8:32 am
This is a good thread with a lot to unpack, but as I re-read some posts, what I thought was a thread about the very proper advice to consider the behavior of the portfolio as a whole rather than focusing on its individual parts, seems at times to devolve into a simple refrain of advising the use of long-term bonds for investors with a "long time horizon." But if the original spirit of this thread prevails, that would not be the main takeaway, and it does contradict the original premise of assessing the portfolio as a whole.
... I disagree. It's a lousy thread that appears to be just be someone arguing why they believe in MPT/MVO portfolios, railing against what they imagine someone else means by the word "safety", and loosely arguing they like long-term bonds without ever really saying so. I suspect because (like most any MVO portfolio) any specific recommendation would be time period sensitive, of dubious past results, and unknowable future results. The argument would have to be narrowed to a specific claim rather than waxing on about what they think other people should think or arguing over the definition of words for the sake of an argument.
I can understand that perspective. Perhaps I am forumulating specific claims even though I am not reading them explicitly in order to get something for my time. Yes, there are limitations in using data, but we can assess certain generalities and determine for ourselves if we think they will hold in the future, our confidence in that, potential impacts if we are wrong, sensitivity when things differ, etc.--a good starting point.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by 305pelusa » Tue Jun 11, 2019 8:56 am

vineviz wrote:
Tue Jun 11, 2019 8:29 am
305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
First, I'm admittedly showing my annoyance at the use of ad hominem arguments and semantic quibbles as a means of avoiding discussion around the actual points I raised in the OP.

Second, the use of sarcasm and/or hyperbole isn't the same as committing a straw man fallacy.

Third, can you provide an interpretation of "you are over-thinking this" that can't be reasonably interpreted as an appeal to anti-intellectualism?
To your first point, I agree that I am being petty. It's half kidding half serious. Please, don't take it as meaning your point is diminished.

To your second point, you unequivocally committed the strawman fallacy. You distorted the view of "you're overthinking this" into " you should never want to learn something new" hoping the absurdity of the latter somehow says anything about the former. If you cannot see it, I honestly question your unbiased ability to determine a fallacy. This one is clear cut.

To your third point, overthinking does NOT mean anti-intellectualism; it means you're spending too much intellectual resource on an issue that is going to give you little returns for it or otherwise does not matter.

The fine line here is that you DO think it's worthwhile so to you, it sounds like anti-intellectualism. But I doubt Call_Me_Op meant "hey stop trying to learn something new" and rather "I don't think this one matters as much as you think it does".

At least that's my interpretation.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 9:06 am

Dialectical Investor wrote:
Tue Jun 11, 2019 8:32 am
This is a good thread with a lot to unpack, but as I re-read some posts, what I thought was a thread about the very proper advice to consider the behavior of the portfolio as a whole rather than focusing on its individual parts, seems at times to devolve into a simple refrain of advising the use of long-term bonds for investors with a "long time horizon." But if the original spirit of this thread prevails, that would not be the main takeaway, and it does contradict the original premise of assessing the portfolio as a whole.
It's possible that I'm guilty of contributing to the thread drift by returning to questions about long-term bonds instead of focusing on the logical fallacy in more general terms.

I agree with you, and in my opinion the main thing that investors should takeaway from this thread is the key insight of Modern Portfolio Theory: an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 9:16 am

Call_Me_Op wrote:
Tue Jun 11, 2019 8:43 am
Adding (high-quality) bonds to a portfolio increases its safety. This may not sound like a particularly sophisticated statement - but it is correct.
This is an example of the kind of generalization to which I was referring in the original post.

Adding bonds to a portfolio MIGHT increase its safety, but it doesn't always. This is true whether the bonds are "high-quality" or not.

Furthermore, adding the "safest" bonds may or may not be the way to produce the "safest" portfolio.

I wrote the OP because I think that investors can benefit from thinking more clearly about what portfolio outcome they want to achieve and more objectively about the most efficient way to achieve that outcome. "Bonds are for safety" might sometimes point people in the right general direction, but I think we can reasonably aim higher than that.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by pdavi21 » Tue Jun 11, 2019 9:18 am

vineviz wrote:
Tue Jun 11, 2019 8:29 am
305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
First, I'm admittedly showing my annoyance at the use of ad hominem arguments and semantic quibbles as a means of avoiding discussion around the actual points I raised in the OP.

Second, the use of sarcasm and/or hyperbole isn't the same as committing a straw man fallacy.

Third, can you provide an interpretation of "you are over-thinking this" that can't be reasonably interpreted as an appeal to anti-intellectualism?
You operate on the bigger fallacy of uncorrelated "asset classes" boosting risk adjusted returns. Really, your asset classes (small value, long term treasuries, multifactor, etc.) are such a small slice of the market that their behavior is very likely to be random and vary based on fund choice (index, holdings, methods, expenses). You take this random behavior and the resultant low correlation in backtesting and project it onto the future without using logical deduction to back it up, rather only selective backtesting.

So it would be hypocritical to penalize others for this fallacy when you push yours.

EDIT: But I agree, "Bonds are for Safety" is a logical fallacy depending on how one interprets the grammar/"safety".

Also, why do you always respond to people calling them amateurs? What is the point in that? If you are an expert, your arguments will speak for themselves.
"We spend a great deal of time studying history, which, let's face it, is mostly the history of stupidity." -Stephen Hawking

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 9:37 am

pdavi21 wrote:
Tue Jun 11, 2019 9:18 am
You operate on the bigger fallacy of uncorrelated "asset classes" boosting risk adjusted returns.
You think that the core tenet of modern portfolio theory (and most financial economics) is based on a fallacy? Really?
pdavi21 wrote:
Tue Jun 11, 2019 9:18 am
Also, why do you always respond to people calling them amateurs?
Do I? I don't recall calling anyone an "amateur", and certainly not in a pejorative sense. But if I did, please point it out because I owe someone an apology.

Then maybe we can get back on-topic.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by pdavi21 » Tue Jun 11, 2019 11:10 am

vineviz wrote:
Tue Jun 11, 2019 9:37 am
You think that the core tenet of modern portfolio theory (and most financial economics) is based on a fallacy? Really?
No. The fallacy is your "asset classes" aren't asset classes. They are tiny pieces of asset classes with capitalizations often smaller than one large company. The fallacy is also that your uncorrelated assets are actually "uncorrelated" going forward or that, if they are, the lack of correlation isn't simply due to the random effects of holding a tiny slice of the market and the resultant uncompensated risks of varying results based on how that slice is determined.

The fallacy has nothing to do with the academic suggestions in the "Modern Portfolio Theory". That's a deflection away from the fallacy I was referring to.

...but "Modern Portfolio Theory" is also flawed because, in practice, it does require backtesting to project future risk and correlations which is largely predictive. This is a huge criticism of Modern Portfolio Theory, and it is an academic "Theory" as stated in it's name and not an investment guide.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 11:23 am

pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
No. The fallacy is your "asset classes" aren't asset classes.
I can't figure out what to make of this statement in general. I certainly don't see how it relates to the notion that an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return.

Which asset classes do you think aren't "asset classes"? What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not? How many asset classes are there?

And what asset classes do you think I invented?
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
...but "Modern Portfolio Theory" is also flawed because, in practice, it does require backtesting to project future risk and correlations which is largely predictive. This is a huge criticism of Modern Portfolio Theory, and it is an academic "Theory" as stated in it's name and not an investment guide.
This is not a criticism that financial economists take seriously, so I'm curious what evidence you have that you think invalidates MPT.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by pdavi21 » Tue Jun 11, 2019 11:38 am

vineviz wrote:
Tue Jun 11, 2019 11:23 am
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
No. The fallacy is your "asset classes" aren't asset classes.
I can't figure out what to make of this statement in general. I certainly don't see how it relates to the notion that an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return.

Which asset classes do you think aren't "asset classes"? What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not? How many asset classes are there?

And what asset classes do you think I invented?
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
...but "Modern Portfolio Theory" is also flawed because, in practice, it does require backtesting to project future risk and correlations which is largely predictive. This is a huge criticism of Modern Portfolio Theory, and it is an academic "Theory" as stated in it's name and not an investment guide.
This is not a criticism that financial economists take seriously, so I'm curious what evidence you have that you think invalidates MPT.
I think the reason you are confused is because you are only reading the points in my points that sound odd out of context and ignoring my supporting statements. This is known as cherry picking which is a good way to defend logical fallacies.

EDIT: but that's fine. I will continue to believe that tiny slices of an asset class are not asset classes and that their performance does have a large random component, and you can continue to believe otherwise. Performance is so random that two opinions can both be rational without guaranteeing any type of relative gain/loss, because at the end of the day, the market behaves irrationally. Perhaps, "Bonds are for safety" can be considered rational as well. If safe bonds were the best performers over the next decade, it would seem very rational indeed in backtests.
"We spend a great deal of time studying history, which, let's face it, is mostly the history of stupidity." -Stephen Hawking

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 11:46 am

pdavi21 wrote:
Tue Jun 11, 2019 11:38 am
vineviz wrote:
Tue Jun 11, 2019 11:23 am
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
No. The fallacy is your "asset classes" aren't asset classes.
I can't figure out what to make of this statement in general. I certainly don't see how it relates to the notion that an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return.

Which asset classes do you think aren't "asset classes"? What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not? How many asset classes are there?

And what asset classes do you think I invented?
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
...but "Modern Portfolio Theory" is also flawed because, in practice, it does require backtesting to project future risk and correlations which is largely predictive. This is a huge criticism of Modern Portfolio Theory, and it is an academic "Theory" as stated in it's name and not an investment guide.
This is not a criticism that financial economists take seriously, so I'm curious what evidence you have that you think invalidates MPT.
I think the reason you are confused is because you are only reading the points in my points that sound odd out of context and ignoring my supporting statements. This is known as cherry picking which is a good way to defend logical fallacies.
Maybe, but it may also have something to do with my requests for clarification being unanswered. I'll repeat them:

1) Which asset classes do you think aren't "asset classes"?

2) What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not?

3) How many asset classes are there?

4) And what asset classes do you think I invented?

5) What evidence you have that you think invalidates MPT.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by bgf » Tue Jun 11, 2019 11:49 am

vineviz wrote:
Tue Jun 11, 2019 9:37 am
pdavi21 wrote:
Tue Jun 11, 2019 9:18 am
You operate on the bigger fallacy of uncorrelated "asset classes" boosting risk adjusted returns.
You think that the core tenet of modern portfolio theory (and most financial economics) is based on a fallacy?
several fallacies really. i do and so do many others. it is no secret that the statistical tools of the MPT toolbox require assumptions that objectively conflict with the behavior of real markets.
“TE OCCIDERE POSSUNT SED TE EDERE NON POSSUNT NEFAS EST"

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 12:00 pm

bgf wrote:
Tue Jun 11, 2019 11:49 am
vineviz wrote:
Tue Jun 11, 2019 9:37 am
pdavi21 wrote:
Tue Jun 11, 2019 9:18 am
You operate on the bigger fallacy of uncorrelated "asset classes" boosting risk adjusted returns.
You think that the core tenet of modern portfolio theory (and most financial economics) is based on a fallacy?
several fallacies really. i do and so do many others. it is no secret that the statistical tools of the MPT toolbox require assumptions that objectively conflict with the behavior of real markets.
The core tenet of MPT that I was referring to was this: "an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return".

What is the logical fallacy (be specific please, because I want to understand you clearly) upon which that tenet depends?

EDIT: Also, please be specific about whether you are referring to MPT or CAPM if you can. I say that because I suspect that there is some possibility you are speaking about MPT but really mean CAPM.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by pdavi21 » Tue Jun 11, 2019 12:05 pm

vineviz wrote:
Tue Jun 11, 2019 11:46 am
pdavi21 wrote:
Tue Jun 11, 2019 11:38 am
vineviz wrote:
Tue Jun 11, 2019 11:23 am
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
No. The fallacy is your "asset classes" aren't asset classes.
I can't figure out what to make of this statement in general. I certainly don't see how it relates to the notion that an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return.

Which asset classes do you think aren't "asset classes"? What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not? How many asset classes are there?

And what asset classes do you think I invented?
pdavi21 wrote:
Tue Jun 11, 2019 11:10 am
...but "Modern Portfolio Theory" is also flawed because, in practice, it does require backtesting to project future risk and correlations which is largely predictive. This is a huge criticism of Modern Portfolio Theory, and it is an academic "Theory" as stated in it's name and not an investment guide.
This is not a criticism that financial economists take seriously, so I'm curious what evidence you have that you think invalidates MPT.
I think the reason you are confused is because you are only reading the points in my points that sound odd out of context and ignoring my supporting statements. This is known as cherry picking which is a good way to defend logical fallacies.
Maybe, but it may also have something to do with my requests for clarification being unanswered. I'll repeat them:

1) Which asset classes do you think aren't "asset classes"?

2) What do you think the criteria is for deciding whether a group of assets constitutes a "class" or not?

3) How many asset classes are there?

4) And what asset classes do you think I invented?

5) What evidence you have that you think invalidates MPT.
1-5 Are subject to my opinion
1. See 2-5
2. Is it an asset (subjective)? Is it unique "enough" to be a class (subjective)?
3. For me there are 2: Global stocks and global bonds. Currencies, commodities, physical property, are probably also asset classes, but I don't know how to explain/can't remember exactly why I am excluding them.
4. Zero. You did promote some though. Factors are not an asset class, and neither are funds that target factors. Long term treasuries are not an asset class. The past performance of these classes are not unique enough against the backdrop of global stocks or global bonds to be considered statistically relevant when volatility and other random risks are taken into account.
5. I have no evidence that invalidates MPT, much like you have no evidence that one particular way to implement MPT is the correct way or that another is an incorrect way. It is an academic theory and not an investment guide.
"We spend a great deal of time studying history, which, let's face it, is mostly the history of stupidity." -Stephen Hawking

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 12:24 pm

pdavi21 wrote:
Tue Jun 11, 2019 12:05 pm
2. Is it an asset (subjective)? Is it unique "enough" to be a class (subjective)?
3. For me there are 2: Global stocks and global bonds. Currencies, commodities, physical property, are probably also asset classes, but I don't know how to explain/can't remember exactly why I am excluding them.[/quite]

Here I'm just going to observe that there is an internal inconsistency with conceding that your definition of "asset class" is subjective (and therefore arbitrary) and accusing someone else of using the wrong definition of "asset class".
pdavi21 wrote:
Tue Jun 11, 2019 12:05 pm
The past performance of these classes are not unique enough against the backdrop of global stocks or global bonds to be considered statistically relevant when volatility and other random risks are taken into account.
Here I think the argument veers into the dangerous territory of presuming that the world's investors are wrong and/or stupid. Most investors view the risks of US Treasury bonds as being fundamentally different from those of high-yield emerging markets corporate bonds, and any competent statistician could quickly demonstrate that those differences are statistically significant.

Most investors are not blind, and all statisticians are not incompetent.
"Far more money has been lost by investors preparing for corrections than has been lost in corrections themselves." ~~ Peter Lynch

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by pdavi21 » Tue Jun 11, 2019 12:31 pm

vineviz wrote:
Tue Jun 11, 2019 12:24 pm
Here I'm just going to observe that there is an internal inconsistency with conceding that your definition of "asset class" is subjective (and therefore arbitrary) and accusing someone else of using the wrong definition of "asset class".

Here I think the argument veers into the dangerous territory of presuming that the world's investors are wrong and/or stupid. Most investors view the risks of US Treasury bonds as being fundamentally different from those of high-yield emerging markets corporate bonds, and any competent statistician could quickly demonstrate that those differences are statistically significant.

Most investors are not blind, and all statisticians are not incompetent.
1. You are correct. I am sorry for singling you out. I guess I was sort of underhandedly doing a similar thing to you as you are doing to the "bonds are for safety" crowd.

2. Which two examples behave more differently?: A)Long term treasury and emerging market corporate bond or B) Microsoft Stock and GE stock. I would guess that Microsoft and GE were larger fractions of the total global stock market (or US tilted if global stocks were less invest-able at the time) in 2000 than LTT and Emerging Market Corporate Bonds are of the global bond market today (or of US bond market in 2000). That is only a guess, but please correct me if it was wrong.

EDIT: I do agree that Long Term Treasuries and Corporate Emerging Markets bonds have logical reasons to behave differently over short term intervals. However, their long term performance has probably been quite similar because they are both high risk bonds. One has high duration risk, and one has high credit risk. MPT says higher risk = higher expected return, so if one found LTT and EMJB with an equivalent level of risk (I don't know how you calculate that), MPT would suggest the long term expected performance is very similar.

EDIT: I guess that brings us to another fallacy: that short term correlation matters more than long term correlation. If you calculate over the period 1979 to 2019 using a decade as the time interval, LTT are more correlated to stocks than the total bond market [is to stocks].
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by bgf » Tue Jun 11, 2019 1:01 pm

vineviz wrote:
Tue Jun 11, 2019 12:00 pm
bgf wrote:
Tue Jun 11, 2019 11:49 am
vineviz wrote:
Tue Jun 11, 2019 9:37 am
pdavi21 wrote:
Tue Jun 11, 2019 9:18 am
You operate on the bigger fallacy of uncorrelated "asset classes" boosting risk adjusted returns.
You think that the core tenet of modern portfolio theory (and most financial economics) is based on a fallacy?
several fallacies really. i do and so do many others. it is no secret that the statistical tools of the MPT toolbox require assumptions that objectively conflict with the behavior of real markets.
The core tenet of MPT that I was referring to was this: "an asset’s risk and return should not be assessed by itself, but by how it contributes to a portfolio’s overall risk and return".

What is the logical fallacy (be specific please, because I want to understand you clearly) upon which that tenet depends?

EDIT: Also, please be specific about whether you are referring to MPT or CAPM if you can. I say that because I suspect that there is some possibility you are speaking about MPT but really mean CAPM.
Markowitz's optimal portfolio theory, Sharpe's CAPM, Thorp's/Black Scholes option pricing derivation, all explicitly require assumptions about markets that are objectively not true. This doesn't mean they aren't sometimes useful; it just means that you need to think about to what extent they might be useful, when they might be useful, what the margin of error is, and under what conditions you know that they won't be very helpful at all, or could potentially be disastrous.

MPT assumes that you can take past price changes of a collection of different securities, for a given period of time, and use statistical tools to maximize or optimize your selection of those securities for a given period of time in the future. The problem is that: the actual behavior of price changes in markets is too extreme; your data set is incomplete, ie, not the sample space; price changes don't fit the normal distribution; they aren't independent of each other; they swing to extremes too often; when they swing to extremes they often do so in clusters; their volatility is not constant; price changes do not happen in continuous time, meaning there are gaps/jumps; and probably others i can't think of off the top of my head.

ive spent enough time on this forum now to basically glance at a thread and place it in the "oh, this is helpful bucket" or the "oh, this is another intellectual crossword puzzle thread that is interesting only as an academic exercise."
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Northern Flicker » Tue Jun 11, 2019 1:31 pm

One way to include both time frames in one's Investment portfolio is to not use TBM as their only FI asset. Sorry for all you three funders but while easy it ignores the short term concerns. Just break that TBM into it's components and both short and lifetime concerns can be addressed.
This is only required if holding in a taxable account, usually not the best place for bonds anyway.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Doc » Tue Jun 11, 2019 1:41 pm

Northern Flicker wrote:
Tue Jun 11, 2019 1:31 pm
One way to include both time frames in one's Investment portfolio is to not use TBM as their only FI asset. Sorry for all you three funders but while easy it ignores the short term concerns. Just break that TBM into it's components and both short and lifetime concerns can be addressed.
This is only required if holding in a taxable account, usually not the best place for bonds anyway.
No. Short term Treasuries for example are very tax efficient because of the low yield and state tax exemption. Also one should not let the taxman drive the asset allocation decision. If you lose your job and need cash would you rather sell stock and pay capital gains instead of selling some T-Bills to cover living expenses. And If you lost your job you may very well be in a zero tax bracket anyway.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by columbia » Tue Jun 11, 2019 2:02 pm

Doc wrote:
Tue Jun 11, 2019 1:41 pm
Northern Flicker wrote:
Tue Jun 11, 2019 1:31 pm
One way to include both time frames in one's Investment portfolio is to not use TBM as their only FI asset. Sorry for all you three funders but while easy it ignores the short term concerns. Just break that TBM into it's components and both short and lifetime concerns can be addressed.
This is only required if holding in a taxable account, usually not the best place for bonds anyway.
No. Short term Treasuries for example are very tax efficient because of the low yield and state tax exemption. Also one should not let the taxman drive the asset allocation decision. If you lose your job and need cash would you rather sell stock and pay capital gains instead of selling some T-Bills to cover living expenses. And If you lost your job you may very well be in a zero tax bracket anyway.
Agreed. In a perfect world, one wouldn’t hold bonds in taxable, but life tends to happen. Interestingly, this also speaks to the premise of the thread: the idea that there is one optimal approach for all is misguided.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 2:07 pm

columbia wrote:
Tue Jun 11, 2019 2:02 pm
Interestingly, this also speaks to the premise of the thread: the idea that there is one optimal approach for all is misguided.
That is NOT a premise of this thread.

In fact it’s the opposite of the premise of this thread.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 2:12 pm

bgf wrote:
Tue Jun 11, 2019 1:01 pm
MPT assumes that you can take past price changes of a collection of different securities, for a given period of time, and use statistical tools to maximize or optimize your selection of those securities for a given period of time in the future.
This is what I feared: MPT does NOT assume this. Nor does CAPM for that matter.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by willthrill81 » Tue Jun 11, 2019 2:19 pm

vineviz wrote:
Tue Jun 11, 2019 2:12 pm
bgf wrote:
Tue Jun 11, 2019 1:01 pm
MPT assumes that you can take past price changes of a collection of different securities, for a given period of time, and use statistical tools to maximize or optimize your selection of those securities for a given period of time in the future.
This is what I feared: MPT does NOT assume this.
Modern portfolio theory (MPT), or mean-variance analysis, is a mathematical framework for assembling a portfolio of assets such that the expected return is maximized for a given level of risk. It is a formalization and extension of diversification in investing, the idea that owning different kinds of financial assets is less risky than owning only one type. Its key insight is that an asset's risk and return should not be assessed by itself, but by how it contributes to a portfolio's overall risk and return. It uses the variance of asset prices as a proxy for risk.
https://en.wikipedia.org/wiki/Modern_portfolio_theory

How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by dbr » Tue Jun 11, 2019 2:27 pm

vineviz wrote:
Tue Jun 11, 2019 2:12 pm
bgf wrote:
Tue Jun 11, 2019 1:01 pm
MPT assumes that you can take past price changes of a collection of different securities, for a given period of time, and use statistical tools to maximize or optimize your selection of those securities for a given period of time in the future.
This is what I feared: MPT does NOT assume this. Nor does CAPM for that matter.
There is an interesting quibble here about what is assumed by MPT and what rises to a higher level of purpose. If it is not the purpose of modern portfolio theory to optimize a selection of investments for a given period of time in the future what reason would one have to even engage in the analysis? But, I will grant you simply describing the past while having no interest in the future might be interesting to someone. On the other hand identifying general past behavior and optimums in past behavior seems like an odd pastime for someone who has no interest in the future.

The author(s) of this Wikipedia article perhaps don't actually say in so many words that the purpose of MPT is to guide investment strategy for a future period, but the language sure seems implicit behind virtually every line that future investment is the point and purpose of the whole endeavor. Maybe you disagree. Nothing wrong with that. https://en.wikipedia.org/wiki/Modern_portfolio_theory

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by bgf » Tue Jun 11, 2019 2:53 pm

vineviz wrote:
Tue Jun 11, 2019 2:12 pm
bgf wrote:
Tue Jun 11, 2019 1:01 pm
MPT assumes that you can take past price changes of a collection of different securities, for a given period of time, and use statistical tools to maximize or optimize your selection of those securities for a given period of time in the future.
This is what I feared: MPT does NOT assume this. Nor does CAPM for that matter.
if you come back with "expected return" i might die.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by HomerJ » Tue Jun 11, 2019 3:24 pm

vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Economics isn't a science like physics.

There are no repeatable experiments, there are EXTREMELY limited data points, and human emotions and human laws (which change all the time) are heavily involved.

I agree when he says you're over-thinking this.

But that's just my opinion, of course.
305pelusa wrote:
Tue Jun 11, 2019 8:56 am
To your third point, overthinking does NOT mean anti-intellectualism; it means you're spending too much intellectual resource on an issue that is going to give you little returns for it or otherwise does not matter.
This. Keep it simple.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Doc » Tue Jun 11, 2019 3:37 pm

columbia wrote:
Tue Jun 11, 2019 2:02 pm
Agreed. In a perfect world, one wouldn’t hold bonds in taxable, but life tends to happen. Interestingly, this also speaks to the premise of the thread: the idea that there is one optimal approach for all is misguided.
"(O)ne wouldn't hold bonds in taxable" Huh?

According to the Bogleheads Wiki with the order of most tax efficient at the top:
Efficient

Low-yield money market, cash, short-term bond funds
Tax-managed stock funds
Large-cap and total-market stock index funds

...
https://www.bogleheads.org/wiki/Tax-eff ... _placement

If you want the most tax efficient placement of your fixed income you need to give up the three fund portfolio mantra and split your fixed income into pieces so that you can get the most tax efficient placement. At the same time you can get improved performance of your total portfolio like having long Treasuries for very high equity asset allocations.

You can also currently put the short part into T-bills in taxable and earn more than a five year Treasury note while getting inflation protection thrown in for free. Nice emergency fund isn't it.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 3:54 pm

willthrill81 wrote:
Tue Jun 11, 2019 2:19 pm
How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
MPT is much more fundamental than many people think it is, and the development and proof of it can bit complex.

The core assumption is really only that investors are risk averse, and the core prediction is that investors will accept a higher-risk portfolio only if they expect a higher return in exchange.

That's pretty much it.

It is true that in order to put MPT into practice (or to test its prediction), additional tools are needed. It's common to presume that MPT actually specifies or requires the use of variance as the measure of risk, but this is merely a convention: MPT itself is agnostic about both what the measure of risk is and how the investor arrives at their expectation of it.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by All Seasons » Tue Jun 11, 2019 3:59 pm

This whole thread can be summed up most succinctly by simply saying that the behaviour of the portfolio as a whole is more important than the behaviour of any individual asset or asset class within it. I don’t think any sensible person will disagree with that. It’s a gestalt perspective. No need to be so verbose to communicate this concept. Long winded tangents with excessive intellectual posturing are what are causing the tumult in this thread.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by bgf » Tue Jun 11, 2019 4:17 pm

vineviz wrote:
Tue Jun 11, 2019 3:54 pm
willthrill81 wrote:
Tue Jun 11, 2019 2:19 pm
How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
MPT is much more fundamental than many people think it is, and the development and proof of it can bit complex.

The core assumption is really only that investors are risk averse, and the core prediction is that investors will accept a higher-risk portfolio only if they expect a higher return in exchange.

That's pretty much it.

It is true that in order to put MPT into practice (or to test its prediction), additional tools are needed. It's common to presume that MPT actually specifies or requires the use of variance as the measure of risk, but this is merely a convention: MPT itself is agnostic about both what the measure of risk is and how the investor arrives at their expectation of it.
this was a non-answer and a dodge.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by fennewaldaj » Tue Jun 11, 2019 4:33 pm

vineviz wrote:
Tue Jun 11, 2019 11:46 am

1) Which asset classes do you think aren't "asset classes"?
This doesn't reflect my opinion but I know there are academics who don't consider factors asset classes. This was discussed in the practitioners guild to asset allocation by by William Kinlaw (Author), Mark P. Kritzman (Author), David Turkington (Author). They would not consider small value stocks a separate asset class for example. I am not sure if they consider long term and short term treasuries separate asset classes.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Northern Flicker » Tue Jun 11, 2019 4:46 pm

No. Short term Treasuries for example are very tax efficient because of the low yield and state tax exemption.
As long as you don’t have to hold stock in a tax-deferred account to make room for the short-term treasuries in taxable space that is true.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by BHUser27 » Tue Jun 11, 2019 4:55 pm

Buy CDs. Done. (Enter Kevin.)

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 6:24 pm

bgf wrote:
Tue Jun 11, 2019 4:17 pm
vineviz wrote:
Tue Jun 11, 2019 3:54 pm
willthrill81 wrote:
Tue Jun 11, 2019 2:19 pm
How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
MPT is much more fundamental than many people think it is, and the development and proof of it can bit complex.

The core assumption is really only that investors are risk averse, and the core prediction is that investors will accept a higher-risk portfolio only if they expect a higher return in exchange.

That's pretty much it.

It is true that in order to put MPT into practice (or to test its prediction), additional tools are needed. It's common to presume that MPT actually specifies or requires the use of variance as the measure of risk, but this is merely a convention: MPT itself is agnostic about both what the measure of risk is and how the investor arrives at their expectation of it.
this was a non-answer and a dodge.
It’s the best answer that question can get, I’m afraid.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by vineviz » Tue Jun 11, 2019 6:26 pm

fennewaldaj wrote:
Tue Jun 11, 2019 4:33 pm
vineviz wrote:
Tue Jun 11, 2019 11:46 am

1) Which asset classes do you think aren't "asset classes"?
This doesn't reflect my opinion but I know there are academics who don't consider factors asset classes. This was discussed in the practitioners guild to asset allocation by by William Kinlaw (Author), Mark P. Kritzman (Author), David Turkington (Author). They would not consider small value stocks a separate asset class for example. I am not sure if they consider long term and short term treasuries separate asset classes.
I’m not sure I know any academics who literally consider factors to be an asset class.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by fennewaldaj » Tue Jun 11, 2019 6:31 pm

vineviz wrote:
Tue Jun 11, 2019 6:26 pm
fennewaldaj wrote:
Tue Jun 11, 2019 4:33 pm
vineviz wrote:
Tue Jun 11, 2019 11:46 am

1) Which asset classes do you think aren't "asset classes"?
This doesn't reflect my opinion but I know there are academics who don't consider factors asset classes. This was discussed in the practitioners guild to asset allocation by by William Kinlaw (Author), Mark P. Kritzman (Author), David Turkington (Author). They would not consider small value stocks a separate asset class for example. I am not sure if they consider long term and short term treasuries separate asset classes.
I’m not sure I know any academics who literally consider factors to be an asset class.
I am probably not stating their case very well but essentially they were saying factors are really trading strategies not asset classes. They consider Small to maybe be an exception (because the characteristics of the group are more stable). But they did not consider a value fund a separate asset class than a blend fund. It seems at least many practitioners do treat a value fund as a separate asset class.

I struggled a fair bit with that book for some reason so its possible I am missing their point.
Last edited by fennewaldaj on Tue Jun 11, 2019 7:35 pm, edited 1 time in total.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by willthrill81 » Tue Jun 11, 2019 7:26 pm

vineviz wrote:
Tue Jun 11, 2019 6:24 pm
bgf wrote:
Tue Jun 11, 2019 4:17 pm
vineviz wrote:
Tue Jun 11, 2019 3:54 pm
willthrill81 wrote:
Tue Jun 11, 2019 2:19 pm
How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
MPT is much more fundamental than many people think it is, and the development and proof of it can bit complex.

The core assumption is really only that investors are risk averse, and the core prediction is that investors will accept a higher-risk portfolio only if they expect a higher return in exchange.

That's pretty much it.

It is true that in order to put MPT into practice (or to test its prediction), additional tools are needed. It's common to presume that MPT actually specifies or requires the use of variance as the measure of risk, but this is merely a convention: MPT itself is agnostic about both what the measure of risk is and how the investor arrives at their expectation of it.
this was a non-answer and a dodge.
It’s the best answer that question can get, I’m afraid.
The answer that I took away is that MPT cannot be implemented without using some measure of risk, and logically this measure(s) can only come from the past.
JoMoney wrote:
Tue Jun 11, 2019 8:41 am
Dialectical Investor wrote:
Tue Jun 11, 2019 8:32 am
This is a good thread with a lot to unpack, but as I re-read some posts, what I thought was a thread about the very proper advice to consider the behavior of the portfolio as a whole rather than focusing on its individual parts, seems at times to devolve into a simple refrain of advising the use of long-term bonds for investors with a "long time horizon." But if the original spirit of this thread prevails, that would not be the main takeaway, and it does contradict the original premise of assessing the portfolio as a whole.
... I disagree. It's a lousy thread that appears to be just be someone arguing why they believe in MPT/MVO portfolios, railing against what they imagine someone else means by the word "safety", and loosely arguing they like long-term bonds without ever really saying so. I suspect because (like most any MVO portfolio) any specific recommendation would be time period sensitive, of dubious past results, and unknowable future results. The argument would have to be narrowed to a specific claim rather than waxing on about what they think other people should think or arguing over the definition of words for the sake of an argument.
:thumbsup
Last edited by willthrill81 on Tue Jun 11, 2019 7:27 pm, edited 1 time in total.
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Ferdinand2014 » Tue Jun 11, 2019 7:26 pm

305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
+1

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by Ferdinand2014 » Tue Jun 11, 2019 7:33 pm

305pelusa wrote:
Tue Jun 11, 2019 8:56 am
vineviz wrote:
Tue Jun 11, 2019 8:29 am
305pelusa wrote:
Tue Jun 11, 2019 8:23 am
vineviz wrote:
Tue Jun 11, 2019 8:14 am
Call_Me_Op wrote:
Tue Jun 11, 2019 7:02 am
You are over-thinking this.
Right. Because we never want to learn something new, become too smart, or make decisions that are too well-informed.
Come on man you should know you just made the classic strawman fallacy.

You keep critizing others of logical fallacies (which is fine really) but don't seem to appreciate where you make them yourself
First, I'm admittedly showing my annoyance at the use of ad hominem arguments and semantic quibbles as a means of avoiding discussion around the actual points I raised in the OP.

Second, the use of sarcasm and/or hyperbole isn't the same as committing a straw man fallacy.

Third, can you provide an interpretation of "you are over-thinking this" that can't be reasonably interpreted as an appeal to anti-intellectualism?
To your first point, I agree that I am being petty. It's half kidding half serious. Please, don't take it as meaning your point is diminished.

To your second point, you unequivocally committed the strawman fallacy. You distorted the view of "you're overthinking this" into " you should never want to learn something new" hoping the absurdity of the latter somehow says anything about the former. If you cannot see it, I honestly question your unbiased ability to determine a fallacy. This one is clear cut.

To your third point, overthinking does NOT mean anti-intellectualism; it means you're spending too much intellectual resource on an issue that is going to give you little returns for it or otherwise does not matter.

The fine line here is that you DO think it's worthwhile so to you, it sounds like anti-intellectualism. But I doubt Call_Me_Op meant "hey stop trying to learn something new" and rather "I don't think this one matters as much as you think it does".

At least that's my interpretation.
Yes. I’m finding this thread has become some perverse intellectual gymnastics event with the only person allowed to get the gold medal is the OP.

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Re: The logical fallacy behind "Bonds Are For Safety"

Post by bgf » Tue Jun 11, 2019 7:58 pm

vineviz wrote:
Tue Jun 11, 2019 6:24 pm
bgf wrote:
Tue Jun 11, 2019 4:17 pm
vineviz wrote:
Tue Jun 11, 2019 3:54 pm
willthrill81 wrote:
Tue Jun 11, 2019 2:19 pm
How can MPT be implemented without an estimate of asset prices' variance? And where would such an estimate come from if not historical data?
MPT is much more fundamental than many people think it is, and the development and proof of it can bit complex.

The core assumption is really only that investors are risk averse, and the core prediction is that investors will accept a higher-risk portfolio only if they expect a higher return in exchange.

That's pretty much it.

It is true that in order to put MPT into practice (or to test its prediction), additional tools are needed. It's common to presume that MPT actually specifies or requires the use of variance as the measure of risk, but this is merely a convention: MPT itself is agnostic about both what the measure of risk is and how the investor arrives at their expectation of it.
this was a non-answer and a dodge.
It’s the best answer that question can get, I’m afraid.
ill ask you a similar question. according to markowitz, samuelson, et al, can one optimize a portfolio without 1) data 2) the Gaussian statistical toolkit?
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Re: The logical fallacy behind "Bonds Are For Safety"

Post by LadyGeek » Tue Jun 11, 2019 8:06 pm

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Wiki To some, the glass is half full. To others, the glass is half empty. To an engineer, it's twice the size it needs to be.

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