Constrained MDPs and the reward hypothesis

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It's been a looong ago that I posted on this blog. But this should not mean the blog is dead. Slow and steady wins the race, right? Anyhow, I am back and today I want to write about constrained Markovian Decision Process (CMDPs). The post is prompted by a recent visit of Eugene Feinberg , a pioneer of CMDPs, of our department, and also by a growing interest in CMPDs in the RL community (see this , this , or this paper). For impatient readers, a CMDP is like an MDP except that there are multiple reward functions, one of which is used to set the optimization objective, while the others are used to restrict what policies can do. Now, it seems to me that more often than not the problems we want to solve are easiest to specify using multiple objectives (in fact, this is a borderline tautology!). An example, which given our current sad situation is hard to escape, is deciding what interventions a government should apply to limit the spread of a virus while maintaining economic
6 comments

LaTeX support

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I added the following two lines to the header section of the template of this page:

  <script type="text/javascript"
src="http://www.maths.nottingham.ac.uk/personal/drw/LaTeXMathML.js">
</script>

Suddenly, I can type (almost) anything in latex, e.g. \$a_n\$ becomes $a_n$. Fancy!
(If you do not see anything fancy then either Javascript is disabled in your browser or you are using Internet Explorer without MathML support. In the latter case you may want to download MathPlayer by DesignScience.)

Many thanks for Peter Jipsen the folks who developed ASCIIMathML, which serves as the basis of LaTeXMathML by Douglas R. Woodall. Examples showing what is possible with LatexMathML can be found here. This is an indispensable tool!

The nice thing is that MathML is scaleable:
$E=m c^2$

Comments

  1. SoloGen22 April 2007 at 07:47

    The only problem is that MathML doesn't work with Safari!

    ReplyDelete
  2. Csaba Szepesvári6 May 2007 at 20:29

    True. Firefox might be an alternative for Mac people.

    ReplyDelete
  3. Anonymous22 May 2007 at 11:03

    And Opera.

    How would you do LaTeX equations in high resolution so that they could be printed on t-shirts though?

    ReplyDelete
  4. Csaba Szepesvári24 May 2007 at 20:40

    I would use postscript or pdf assuming you have latex installed on your system.. But MathML fonts are also scalable; use HTML tags for this.

    ReplyDelete
  5. Csaba Szepesvári14 April 2012 at 20:58

    Update to myself: I have switched to MathJax and now I am using the script to be found here:

    http://irrep.blogspot.ca/2011/07/mathjax-in-blogger-ii.html


    The quality is better, though the pages will load slower. But the days of ever increasing computer speed, this should not be a problem.

    Oh, and I hope LaTeX works in the comments, now, too. Let's check: $Q^*(x,a) = \int dP(y|x,a) \left\{ r(x,a,y) + \gamma \max_{a'\in A} Q^*(y,a') \right\}$.

    ReplyDelete
  6. Csaba Szepesvári14 April 2012 at 20:58

    Oh, and Safari now seems to support MathML..

    ReplyDelete

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