Product yield reflects the potential product quality and reliability, which means that
high yield corresponds to good quality and high reliability. Yet consumers usually
couldn’t know the actual yield of the products they purchase. Generally, the products that
consumers get from suppliers are all eligible. Since the quality characteristic of the
eligible products is covered by the specifications, then the observations of quality
characteristic follow truncated normal distribution. In the light of maximum likelihood
estimation, this paper proposes an algorithm for calculating the parameters of full
Gaussian distribution before truncation based on truncated data and estimating product
yield. The confidence interval of the yield result is derived, and the effect of sample
size on the precision of the calculation result is also analyzed. Finally, the
effectiveness of this algorithm is verified by an actual instance.