Saying thanks in the personal statement? Should I include a small thank at the beginning of my personal statement? The thank can long for one line to three lines depends on the specifics it included. In the short version, it can be like this:


  I want to thank my mom, my friend XYZ and the SE community for supporting me all the time.


In the long version, it can be:


  I want to thank my mom for understanding my passion, my friend XYZ for his alacrity to make my works flows better in English, and the SE community as well as other person who I have never met has spent time advising and criticizing every time I come up a new idea.


I should make clear that the school I intend to apply requires me to write a personal statement, separate to the SOP.


  The personal statement should give concrete evidence of your promise as a member of the academic community, giving the committee an image of you as a person.


As a person, not a researcher.
No, a statement of thanks in the form you have described has no place in a statement of purpose.

The statement of purpose should be a concise, focused document. Everything in there should be there for a specific purpose: to convince the readers that you would be a strong addition to their department. Anything that doesn't serve that purpose distracts from that purpose and doesn't belong in there.


  The personal statement should give concrete evidence of your promise as a member of the academic community, giving the committee an image of you as a person.


None of the things you have written in your thanks "give concrete evidence of your promise as a member of the academic community" so they do not belong there.

Besides for being ineffective as part of your application for graduate admissions, it's also somewhat ineffective as an expression of gratitude. Private thanks expressed to the person you are thanking are nice; public thanks (like in a thesis, or a Nobel prize acceptance speech) are also nice. What's the point of thanking someone in a private document, that they're not the intended audience of? If you want to thank your mom, send her a letter, or call her on the phone and thank her.