It shows the patterns of new words introduced as a recurrence and possible frame in each psalm right up to to Psalm 150 and of the reuse of frames used in earlier psalms.
The overall question is - what story do the keywords tell and is the order of the psalms deliberate - an act of redaction, this decided if it can be, purely on the basis of content? Apart from historical speculation, content is all the information I have. Of course we know that the Psalter is well represented at Qumran and that it was the favorite book of the New Testament authors - judging by the number of allusions there.
Are there a few superficial lessons in content?
What we have so far is this:
- Psalm 1 is about: happiness, wickedness, the way, sin, righteousness, and there is a conditional
- Psalm 2: Earth, the stand-alone first person pronoun, the nations, and king
- Psalm 3: many, arising, salvation, and people
- Psalm 4: many, hear, righteous, speak, call, trust, bed, offer
- Psalm 5: many, voice, you (both the stand alone pronoun and in the tone of address - even preposition + second person singular pronoun makes a significant sound at the end of the psalm.)
- Psalm 6: hear, life/soul, time, vexed (O excuses!)
- Psalm 7: righteousness, righteous, conditional, life/soul, evil, toil, salvation, work, persecution, trouble, turning, judgment
That's enough for now - it only gets more complex as the length of the psalms increase. Also I can see where things might be equal that are slightly different - due to the difficulty of automatically parsing the Hebrew. I expect you can see the pattern of frames reaching both forward and back.