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justinluther

"That’s not an upgrade. That’s a hostage situation."

Ask HN: Could online services "flood the zone" of compromised password lists?

What if a majority of online services agreed to all create a lot of fake user profiles in their databases that have random string passwords? Then, when a service gets compromised and passwords are leaked, there are a bunch of useless passwords in the published leak mixed in with the real passwords that might be re-used on other sites.Is there a ratio of fake passwords to real ones that would...

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Re:I Can Tolerate Anything Except the Outgroup on Wednesday September 06, 2023 @01:55PM (#37408610)
The main condition that you're talking about is having a high population. Chicago has a lot of murders because it has a lot of people. The murder rate per capita is a little above 2x the national average, but not an outlier by any means.

Chicago is #28 on the national ranking of murder cities: https://www.cbsnews.com/pictures/murder-map-deadliest-u-s-ci...

It is ranked right in between Chattanooga and Buffalo.

Yes, but you could slightly amend their statement to say "Can you name a non-capitalist government..." to remove the false dichotomy and preserve the original point of the question, right?

Show HN: A Rust Wrapper for the GPT-3 Completions API

https://github.com/justinluther502/writing_helper

I have been experimenting with using the GPT-3 Completions API to co-write blog articles. I wrote this Rust binary to speed up the content generation process.I use two text files. One for prompt text, the second for suffix text. I edit both files in a regular text editor and then just run the executable whenever I want GPT-3 to fill in some content.This isn't commercial-- and you have to have...

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Thanks! In a previous iteration I used some of those solutions, both Heroku and Render. I thought this might be a good use case for Lambda because the API doesn't get called very often, and it's really just one function. Refactoring the backend code to keep the lambda handler skinny seemed to help. If I continue to have problems I will definitely look at these options.
I'm keeping it private for now but might open it up in the future. Thanks!
Thanks! I've also noticed that the pie chart re-rendering is quite busy and visually distracting. But javascript is by far my weakest layer in the whole stack so I've struggled to fiddle with it without breaking it :)
I agree! A video could definitely help, and I will try to change the display of the instructions on small screens.
Thanks for the suggestion! Right now I have attempted to do what you are describing, but the user has to click OK on the initial "welcome" dialog box to get stepped through the tour. If you click outside of the box to close it, you skip the tour. Definitely something to improve.
Thanks very much for the kind words!
Thanks for your feedback! This is on my to-do list of things to fix-- some of the flavors have been developed using monthly returns and some use annual. In both cases the x axis is variance of the periodic returns. Also in some cases the returns are log returns which is also a todo. I will fix it so that the x axis is labeled with the user's choice of risk metric used by the optimizer. Also, I should have mentioned it, but the risk choice isn't implemented in the backend yet so the risk metric choice just defaults to variance for right now.
I believe the idea with mlfinlab is for users to build and test models to predict asset returns. In other words, a tool to generate alpha. I may be wrong about this as I'm not familiar with mlfinlab.

CashGraphs is more oriented towards passive asset allocaters who want to pick a portfolio that has high expected returns for a given risk-tolerance level.

Yes that's definitely a struggle. There is a balancing act involved in getting a set of time series that share 1) a common methodology for calculating index levels and returns, 2) a long lookback period, 3) index levels that account for dividends, 4) freely available and relatively simple to download to csv or other useful format. St Louis FRED database was very useful in this regard. I could definitely make some nicer flavors by using a paid source for historical asset returns but I'm not willing to do that just yet.

The next flavor I make will probably use something from: http://mba.tuck.dartmouth.edu/pages/faculty/ken.french/data_...

And for that one I'd like to use some non-normal distributions and other fancier characteristics.

Thanks for the feedback! I'll try to label the chart a little more clearly. The y axis is expected returns, the x axis is expected riskiness. I show the generated optimal portfolios alongside the original constituent assets that comprise the portfolios. So ideally you want a portfolio up and to the left, but higher-returning securities tend to be riskier.

I found the literature on vine copulas to be helpful, particularly the following presentation: https://www.birs.ca/workshops/2013/13w5146/files/Brechmann.p...

I used that as a helpful guide for ways to create some of the more interesting returns simulations.

Show HN: CashGraphs – A securities portfolio optimizer

https://www.cashgraphs.com/

Hello,This is a portfolio optimizer I made to help select portfolios for my clients. I'm a personal financial adviser. I generally put my clients in a mix of low-fee index funds and ETFs and I use this to set an appropriate allocation based on the client's risk tolerance.I have been working on this as a side project to 1) improve the theoretical underpinnings of my investment recommendations...

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Re:Ask HN: Who wants to be hired? (June 2022) on Wednesday June 01, 2022 @01:14PM (#31584976)

  Location: Charleston, SC
  Remote: Yes
  Willing to relocate: Yes
  Technologies: Vue, Django, Python, R, Tensorflow 1/2. Experienced in sales / finance / MBA / CFA. Hobbyist coding.
  Résumé/CV: https://www.linkedin.com/in/justin-luther-cfa-2897575/
  Email: [email protected]
Thanks!

I like the idea of example buttons, particularly for the cash flow planner. And also maybe a default set of assets and cashflows that would work as a starting point for a common investing case.

Hi HN,

I’m Justin, and I’d like to get some feedback on Indie Adviser. It’s a web app I initially built to support my own independent state-registered investment adviser (RIA) business. I’m now planning to market it to other financial advisers. I’ve set up a dummy login button for HN visitors, so there is no need to create a real account.

It’s designed to complement an adviser’s existing brokerage portal, adding portfolio optimization and cashflow projection tools, as well as some client recordkeeping that I think is specifically useful to RIAs. These are modules typically included in a big-box wealth management firm’s proprietary toolkit. The idea is to help financial advisers go independent using a modular toolkit that can work alongside any brokerage portal. I personally use Interactive Brokers, and that’s the only brokerage connection currently implemented.

The modern portfolio theory optimizer generates mean-risk efficient portfolios (https://en.wikipedia.org/wiki/Modern_portfolio_theory). Modern portfolio theory has been criticized for 1) relying on variance as a risk metric and 2) forcing an assumption that asset returns are normally distributed. The portfolio optimizer solves the first problem by allowing for alternative risk measures such as semi-variance and loss thresholds. I prefer semi-variance as a risk measure because it doesn’t count upside movement as risk. Semi-variance has been traditionally omitted from portfolio optimizers due to the simplicity of calculating plain-old portfolio variance. Portfolio variance doesn’t require a full calculation of the weighted portfolio returns distribution, as long as the covariance matrix of the individual assets is known. But with modern computing, I don’t see any reason to not “upgrade” risk measures. Note: the frontend only has the typical variance risk measure implemented.

To solve the second problem, I use a vine copula model for asset interrelatedness rather than the typical joint normal return distribution assumption. The joint return distribution generated with the copula model is the input to the portfolio optimizer algorithm.

I would very much appreciate any feedback. I’m particularly interested in feedback from any other financial advisers, especially those who do their own portfolio models. I’m also interested in feedback on the web app itself—I’m not a professional so I’m mostly learning as I go. And finally, if you work in institutional portfolio management and are interested in bespoke MPT optimizations, contact me!

Thanks very much! Justin Luther [email protected] https://www.lutherwealth.com