About Hive User Segments

Dear All,

I am currently working on a research project about Hive Ecosystem and Hive Blog. I am still new to the community and exploring all the activities, features and roles on Hive Blog. Although trying hard to understand the community thoroughly, I still have many unsolved questions which I am hoping to get some helps from all of you who are much more experienced and familiar to Hive than I am.

Here is my current list of agents on Hive:

• Downvoters
• Upvoters
• Commenters
• Content Creators
• Developers
• Witnesses
• Investors
• Communities
  Please feel free to correct me if there is any misunderstanding about the Hive user segments

My questions are mainly about Developers, Witnesses and Investors.

Q1: Developers' Proposals
I understand developers can submit proposals on Hive so that users can vote for and decide which one to be invested in. However, I observe that some of the proposals disappear on the list after certain amount of time. Where did they go? Are those proposals completed? Is there any historical data of all the proposals?

Q2: Witnesses' Jobs
According to my knowledge, witnesses on Hive blockchain help create and sign blocks. However, I am not clear about how do they do that? Manually create and sign or is there any automated process involved? Moreover, can they approve transactions and produce blocks based on their own decisions or have to be based on consensus among all witnesses?

Q3: Who Are the Investors?
Investors are critical to the growth of Hive blog. However, I am not clear how to identify or classify who are the investors of Hive blog. Are all whales investors?

Q4: Changes in Reward Mechanism
I am seeing many posts talking about the change made to the voter/content creators reward distribution, from 75/25 to 50/50. However, I wasn't be able to find information about when and what time the change was made.

Q5: Who are the HP Stakeholders?
I read the Hive Whitepaper saying that 15% of the Hive inflation will go to HP stakeholders. However, I am not sure that if the HP stakeholders means all users who owns any amount of HP? Or if the HP stakeholders point to a specific group of users?

Any help or answer would be highly appreciated! I love the fascinating concept of Hive blog and enjoy engaging in the community. Although I am not able to contribute to the community through developing apps or posting frequently, I would like to make Hive known through publishing series of journal articles in the near future.