A Chat with ChatGPT on Spend Rates

I had a chat with ChatGPT(3?) on spend rates. I just wanted to check out what it said. Basically it was cagey, conservative, and disclaimer heavy. I also had to challenge it a bit. Not sure if I could walk up to the prompt and trust what it said. My guess is that in a few years, everything I learned from this blog will be moot but maybe not. Interesting resource.

Here is the chat. I have a comparative chart at the end. Not sure how much fidelity there was to what I got from Chat but then I was moving pretty fast.

Another, and Likely Last, Look at Backward Induction SDP for Spend Rates

My fin-bro David chastises me for sandbagging in my blog but in this post you must take everything after this sentence with a big fat grain of salt. I have no idea if what I am doing here is either correct or legit and the fact that it looks like it works in the end is pretty much dispositive of zip. Plus my notation is sketchy.

Two years ago I tried to do this thing where I inferred optimal spend rates by working backwards from the end of a 30 year interval and used the results of a value function in the last period to help figure out what to spend in the period just prior and then on to the beginning. This is called backward induction and stochastic dynamic programming and is often described as Bellman equations if I have it right. 

Sorta worked then. I went back a week ago to look at my code and I noticed two things: 1) I had no idea what the code was doing, and 2) there were some coding errors. Those two things, combined with incipient dementia (kidding), caused me to decide to exercise my brain and try this again. Silly me. There is no real purpose other than do it and what I noticed in the re-try is that it's a lot of work for results one can get from easier and simpler methods: the juice is probably not worth the squeeze.