Research in the 80's and 90's showed how to construct a pseudorandom
generator from a function that is hard to compute on more than $99\%$
of the inputs. A more recent line of works showed however that if
the generator has small error, then the proof of correctness cannot
be implemented in subclasses of TC$^{0}$, and hence the construction
cannot be applied to the known hardness results. This paper considers
a typical class of pseudorandom generator constructions, and proves
an analogous result for the case of large error.

Please see ack.

Research in the 80's and 90's showed how to construct a pseudorandom
generator from a function that is hard to compute on more than $99\%$
of the inputs. A more recent line of works showed however that if
the generator has small error, then the proof of correctness cannot
be implemented in subclasses of TC$^{0}$, and hence the construction
cannot be applied to the known hardness results. This paper considers
a typical class of pseudorandom generator constructions, and proves
an analogous result for the case of large error.