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Month: June 2021

Misc

People just like to watch

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I was watching a youtube video of how to make bonzai today. And I was think about how to make my own bonzai better. And I felt that it’s just too much work to make it better. I’m content with just having it the way it is now. I realized that I don’t enjoy shaping up my bonzai, not even owning the bonzai is that attractive for me. I probably just want to watch other people making bonzai and want nothing to do with myself. I’m perfect happy with just watching.

I don’t think it’s a unique feeling, because there are so many channels on Youtube about watching other people playing games. Heck, the whole sports industry is watching other people play a game.

So I decided, maybe I will just make videos about me making programming projects. One, I actually like to build project with code. Two, other people might not want to spend the time coding, but enjoy other people building a project.

So look forward to my video, talking about a computer programming projects I will make.

by yangliu3456
Journal

Solving problems in practice

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Several weeks ago, I was watching a Vox video on Covid-19 vaccine distribution. The story was about how rich countries were first in line to get vaccines because they made individual deals with the pharmaceutical companies to invest in research, to guarantee they receive the first batch of vaccines. There was an organization formed for many countries to chip in, so the poor countries can also get vaccines. But the way it worked out is that rich countries both contributed to the organization and made deals with pharmaceuticals companies, since they have the money, so they still end up being first in line for vaccines.

The video ended by wondering why it didn’t work, but fall short to indicate that human behavior is the reason that the original plan didn’t work. When working with any human-generated data, we are required to look at how that data was generated. Sometimes, people approach the data from an objective approach and ignored the human factor. But for many years, humans have greed and desires. An there often isn’t a more deep explanation than, “I want that because I can”. People like to seek reason and wish there is an logical explanation, but we can more often approach from the angle that sometimes people do things for no reason.

by yangliu3456
Journal

Extend the free space on LVM

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I had to reinstall my ubuntu 20.04 server because a boot issue became impossible to fix. After installing the OS, I found that df -lh only give me about 200 GB of space. I had more hard drive. With a little search around, I found that the disk is mounted, but I meant to extended to be more flexible. I just want all the space there.

This post gave a pretty good description of the problem and what to do, but here is commands I used specifically. This post showed how to extend all the free space, without specifying the exact amount of space.

sudo vgs

  VG        #PV #LV #SN Attr   VSize  VFree
  ubuntu-vg   1   1   0 wz--n- <2.73t 2.53t

sudo lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv

  Size of logical volume ubuntu-vg/ubuntu-lv changed from <2.15 TiB (563200 extents) to <2.73 TiB (714879 extents).
  Logical volume ubuntu-vg/ubuntu-lv successfully resize

sudo resize2fs /dev/ubuntu-vg/ubuntu-lv

resize2fs 1.45.5 (07-Jan-2020)
Filesystem at /dev/ubuntu-vg/ubuntu-lv is mounted on /; on-line resizing required
old_desc_blocks = 275, new_desc_blocks = 350
The filesystem on /dev/ubuntu-vg/ubuntu-lv is now 732036096 (4k) blocks long.

df -lh
/dev/mapper/ubuntu--vg-ubuntu--lv  2.7T   11G  2.6T   1% /

by yangliu3456
AI

How to test a hypothesis by AI?

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The traditional hypothesis testing I learned in school involves this:

  1. Stating with null hypothesis, which assumes no effects, and
  2. Alternative hypothesis, which state there is an effect.

So we can make the null hypothesis that “Earth is flat”, and the alternative hypothesis that Earth is not flat.

For humans, we can explore the physical world and design experiments to disapprove the null hypothesis. But for a AI, assuming these is no way for the AI to interact with the world through physics. How we can we truly test the hypothesis?

One way to go about this is find a general consensus amongst human knowledge. For example, using Google search result to see whether human agree on the hypothesis. This of course doesn’t mean that human consensus is the truth. In the early times, the consensus was that “Earth is flat”, and the consensus only changed recently if we consider the whole span of human consensus. It is very likely that the human consensus will change over time.

So what then? Do we believe that if AI cannot interact with the physical world, then it cannot prove or disapprove a hypothesis? Is there any alternative? Is there even an approximation? Is it possible that we can deduce from logic and evidence, that upon the collection of enough evidence and applying proper logic that we can disapprove the null hypothesis without physically interact with the world? Sometimes theoretical physics prove the existence of certain things before experiment verification.

by yangliu3456