In 1 Nephi 10, Joseph Smith removed yea from three examples of “yea even”. In addition to the example here in verse 3, we have these two instances:
This conscious editing by Joseph is found only here in 1 Nephi 10. Elsewhere, he left all other examples of “yea even” unchanged. The original text had 190 examples of “yea even”; besides these three edited examples, there are three accidental copying errors for which yea was lost from the phrase “yea even”. (Each of these three accidental losses involved a preceding you that appears to have interfered with transmitting the following yea. For discussion of these instances, see Alma 42:31, Alma 54:9, and 3 Nephi 3:8.)
The original yea is very characteristic of the Book of Mormon text and is used to clarify the immediately preceding text. Thus the yea should be restored in these three examples in 1 Nephi 10.
Summary: Restore the three cases of “yea even” in 1 Nephi 10:3, 4, 9; the deletion of the yea in this chapter represents stylistic editing on the part of Joseph Smith.