Eliezer b. Hyrcanus is the first Tannaitic master for some of whose sayings we have chains of tradition, that is, authorities who say, “I heard from…” or, more commonly, Rabbi X says/said that Rabbi Y says that R. Eliezer b. Hyrcanus says/said. In addition, some of the Toseftan traditions about Eliezer, like many of those about disputes of the Houses, contain redefinitions of the substance of a dispute, or of the protasis of the pericope, preserving the apodosis just as it appears in the Mishnah. These constitute important evidence about the formation of Eliezer’s sayings; they tell us that a given authority knew and did not accept the specification of an opinion of Eliezer or of a matter about which he and others disputed, as given anonymously, but preferred a different formulation of the matter. Finally, we have, primarily from Judah b. Ilai, a number of opinions for Eliezer which are either consistent with (or contradict) anonymous Mishnaic laws, but which do not appear in the Mishnah in Eliezer’s name.
Jacob Neusner, <i>Eliezer ben Hyrcanus: The Tradition and the Man</i> Part Two (Leiden: E.J. Brill, 1973), 73.