Try to play with dm_control and request a trial license for mujoco. Since the trial license is for local machine, I have to set colab to run locally. Things mostly work okay. I still have some problems here and there (like ffmpeg can’t generate video). I have to install pyopengl and add the following to…
My Gigabyte laptop overheated and hanged a couple of times. I decided to look for solutions. First, it is a good idea to install psensor to monitor the temperatures of the cores. The current core temperature is almost 70 degrees C. I like it hot, and my room temperature is almost 30 C. But probably…
The two concepts machine teaching and inverse RL are closely related. But one is not a special case of another. For machine teaching, the goal is to decide the optimum data set for an algorithm to learn. In other words, given a constraint of teaching cost (that can be proportional to the size of training…
It is a dream about fleeing from HK… I don’t remember how I get there now. But I was asked to attend some event in HK. And not showing up in the entire event was considered to be not loyal enough. My friends predicted that would correspond to a year of jail time. My friend…
Machine learning system fails when the training data distribution is significantly different from testing data. For a “simple” problem like image classification, we can avoid this problem by including sufficient diversity for the training data. But for more complicated real-world problems, such as robotic AI, there are simply too many different possibilities that one cannot…
I didn’t realize that papercite was not working when I moved my WordPress to a new server. It took me a long time to figure out what was wrong. But once I figure out how to debug WordPress, it becomes very easy to fix the problem. To debug, add define(‘WP_DEBUG’, true); define(‘WP_DEBUG_LOG’, true); in wp_config.php…
Counterfactual explanations are proposed and studied in recent years. In logic, counterfactual refers to the scenario when the condition of an if-statement is universally false. Note that the if-statement is universally true when the condition is universally false. So the conclusion is false even though the if-statement holds true always. Counterfactual example in ML refers…
I came across the proof of Perron Frobenius theorem here and it used Banach fixed point theorem. So I spent some time to understand the fixed point theorem from the wiki. Theorem Banach fixed point theorem considers a complete metric space (with metric ) and for any contraction mapping , there will exist a…
I thought I studied this before but can’t find a post from my blog. Byzantine generals problem was named by Leslie Lamport, the creator of LaTex. They consider a distributed consensus problem with the allegory that every general will need to agree on a broadcast message so that they can unify their attacks. It seems…
My Gigabyte hanged again, probably because of overheating. Chrome became super slow after rebooting. It was eventually fixed after reinstalling. That is, sudo apt purge google-chrome-stable rm -rf ~/.config/google-chrome/ and then reinstall by downloading Chrome from another browser. Update: the problem does not seem to be fixed somehow… But turned off hardware acceleration seems…