Jump to content

Talk:Post-modern portfolio theory

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Untitled

[edit]

Article content is completed but is periodically updated. What is the period and frequency of the data which was used to calculate the table in the section Volatility skewness??? The 10 years ending December 2005.

(Wed Oct 3 19:25:36 EDT 2007) —Preceding unsigned comment added by 128.197.42.60 (talk) 23:28, 3 October 2007 (UTC)[reply]

Suggestions: please define the term MAR; a graph of the newly computed efficient frontiers would be helpful. PineHillTechnology 13:25, 3 November 2007 (UTC)PineHillTechnology MAR = Minimum Acceptable Return, or the return required in order to achieve a particular goal, such as, ‘have sufficient pre-tax assets to retire in 15 years’.[reply]

Style

[edit]

This appears to be an essay or paper and needs stylistic adjustment. The endnotes should be wikified. Ben Finn (talk) 18:14, 4 January 2008 (UTC)[reply]

As a layman, I can say that the style is extremely technical. I couldn't understand it, at least from casual skimming. Heavy Joke (talk) 01:52, 28 August 2009 (UTC) It’s as technical as it needs to be for a practitioner to understand. The typical layman would first need to familiarize himself with the principle of modern portfolio theory and it’s application to identifying the trade-offs between the risk and return inherent in investment-portfolio construction.[reply]

Wikify tag

[edit]

The wikify tag on this article says "Please help by adding relevant internal links…". So I did, this morning. Later today, editor Brianmarc removed them all – with no Edit Summary, no explanation, nothing. The tag is still there asking for links. Discuss. Hebrides (talk) 19:24, 9 September 2009 (UTC)[reply]

[edit]

In September 2011, this article was flagged for copyright problems. A comparison between the article and the purported source makes clear that this accusation has merit. For example, the article says:

In 1987 The Pension Research Institute at San Francisco State University developed the practical mathematical algorithms of PMPT that are in use today. These methods provide a framework that recognizes investors’ preferences for upside over downside volatility. At the same time, a more robust model for the pattern of investment returns, the three-parameter lognormal distribution, was introduced.

2001's Managing Downside Risks in Financial Markets says, at page 60:

In 1987, Frank A. Sortino, director of The Pension Research Institute at San Francisco State University, developed the practical mathematical algorithms of PMPT that are in use today. These methods provide a framework that recognizes investors’ preferences for upside over downside volatility. At the same time, a more robust model for the pattern of investment returns, the three-parameter lognormal distribution, was introduced.

This copied and closely paraphrased content continued at great length. I am checking content above this for copyright concerns as well. We will not be able to retain this content unless the procedures at Wikipedia:Donating copyrighted materials are followed. --Moonriddengirl (talk) 20:06, 17 September 2011 (UTC)[reply]

[edit]

Prior content in this article duplicated one or more previously published sources. The material was copied from: Managing Downside Risk in Financial Markets (Quantitative Finance); Sortino, Satchell, et al.. Infringing material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you. Moonriddengirl (talk) 20:10, 17 September 2011 (UTC)[reply]

The donation process is complete, and the content is restored. --Moonriddengirl (talk) 23:58, 22 January 2012 (UTC)[reply]

Claims on the development of PMPT

[edit]

User:FSortino posted the following earlier on the page. As it has not been substantiated at this time, nor is it written in the language appropriate for an encyclopedia I undid the post. However, someone with more knowledge on this matter should look into this and decided how to proceed. I am appending the initial post below:

Postings below by Brian Rom imply he and his associate at his company, Investment technologies, created both Post Modern Portfolio Theory (PMPT) and the Sortino ratio. These claims are both based on one article written by Rom and Kathleen Ferguson in 1993. What Rom fails to disclose is: In September of 1988, Dr. Frank Sortino, acting as Director of the Pension Research Institute (PRI) at San Francisco State University, entered into a licensing agreement with Mr. Rom to develop a user interface for a software program Sortino developed with Dr. Hal Forsey and to market that derivative product. Rom heard the phrase “Post-modern portfolio theory” (PMPT) mentioned at an Ibbotson Associates conference and told Sortino he was going to use it to label the body of knowledge developed at PRI. When the contract was signed in 1988 Mr. Rom knew nothing about the PMPT body of knowledge. Dr. Sortino spent countless hours for years giving Rom tutorials to teach him enough about PMPT for him to market it. Putting a name on the body of knowledge developed at PRI in no way gives Rom the right to claim he had anything to do with developing PMPT. This would be like Alfred Bucherer claiming he created “The Theory of Relativity” because he was the first to coin that phrase in a 1906 paper about Einstein’s research. The PRI agreement with Rom is available at www.pmpt.me and required that Rom’s firm “include the following words on the opening screen: “This product is an extension of a model developed by the Pension Research Institute;” and furthermore, that Rom’s firm (then called SSI) would only be responsible for “designing all Non-Technical Features” and “PRI will be responsible for continuing to develop the Derivatives Technical Features.” The Licensing agreement was not terminated by Rom until November of 1995. Therefore, the entire body of knowledge constituting PMPT that Rom was promoting between 1988 and 1995 was developed at PRI and not by Rom and Ferguson.

Zfeinst (talk) 22:22, 2 September 2015 (UTC)[reply]

The below message is copied from my talk page User talk:Zfeinst#Post-modern portfolio theory and I thought it best to respond here so as to keep all discussions in a single location.

I am glad to see there is discussion going on regarding the work my colleague Hal Forsey and I worked on for the past 34 years. I do not understand why the 1981 contract between Rom and The Pension Research Institute that specifically prevents Rom from making any quantitative changes in the software is of no interest. I would happily send the documents in a pdf file to prove Rom's claims are unjustified. Dr. Frank A. Sortino, Director

In response to Dr. Sortino's comments, I think that such a contract is relevant if it can show that the idea for post-modern portfolio theory (and the Sortino ratio) came from Dr. Sortino and PRI rather than Brian Rom and Investment Technologies. My main issue with the text as it was written (and copied in the prior message in this talk page) is the tone that it takes. Rather than being written as an encyclopedic article, the two paragraphs are written as a quasi-attack on Mr. Rom. Does anyone else have comments on this? Anyone know how to read through a contract to see if it can show who originated a specific idea? That is not my area of expertise. Zfeinst (talk) 02:43, 6 September 2015 (UTC).[reply]
 the post by Dr. Sortino. contains

Lacking in citations, has claims of originality

[edit]

I am not sure there is much interest in the fact, but this article is singularly lacking in citations, albeit contains five endnotes and numerous references. Should there not be a note asking for improvements?

There is a sentence in the article that arouses suspicion: "The term post-modern portfolio theory was created in 1991 by software entrepreneurs Brian M. Rom and Kathleen Ferguson to differentiate the portfolio-construction software developed by their company, Investment Technologies, from those provided by the traditional modern portfolio theory."ArthurOgawa (talk) 05:45, 24 May 2021 (UTC)[reply]