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Let conv be as defined in Equation 9.1. Let 0216-001.gif, 0216-002.gif, . . . , 0216-003.gif be a permutation of 1, 2, . . . , 3j, such that, for each r = 1, . . . , 3j- 1,
0216-004.gif
Define scientists 0216-005.gif, 0216-006.gif, and 0216-007.gif so that for each  s :
0216-008.gif
0216-009.gif
0216-010.gif
Now suppose T is a text for 0216-011.gif. Consider the following two cases.
Case 1: At least 2j + 1 of the scientists in the team consisting of scientists M1, M2, . . . ,M3j converge on T. In this case, it is easy to verify that 0216-012.gif. Moreover, 0216-013.gif (respectively, 0216-014.gif) TxtEx-identifies T if 0216-015.gif (respectively, does not TxtEx-identify T).
Case 2: Not case 1. In this case, 0216-016.gif and 0216-017.gif.
We leave it to the reader to modify the above proof to show the following result, which says that probabilistic identification of languages with probability of success at least 0216-018.gif is the same as team identification of languages with success ratio 0216-019.gif.
9.39 Proposition 0216-020.gif.
Proposition 9.40 below establishes that 0216-021.gif is indeed the cut-off point at which team identification of languages becomes more powerful than identification by a single scientist.
9.40 Proposition 0216-022.gif.
Proof: Let Image-2201.gif be as in the proof of Proposition 8.22. By Lemma 8.23, 0216-023.gif. So we need only show that 0216-024.gif. Consider a team consisting of three scientists M0, M1, and M2. For each 0216-025.gif, scientist Mi behaves as follows: On T[n], Mi outputs the maximum y, if any, such that 0216-026.gif. It is easy to verify that if T is a text for some language in Image-2202.gif, then at least two of the scientists will converge in the limit to a grammar for content(T). Thus, 0216-027.gif.

 
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