Comparison of measured and expected median 3'-UTR lengths in EST libraries from a common sample. A comparison of empirically derived and expected median 3'-UTR length for two groups of related EST libraries. Each set contains 6 libraries from a common tissue sample and targeted transcripts range from 0.5–1 k, 1–2 k, 2–3 k, 3–4 k, 4–5 k and 5–7 k. Expected 3'-UTR length distributions were calculated as described in Methods. The FX0 and HA0 library sets represent EST libraries from pools of tissues from brain and eye, respectively . The correlations between the measured and predicted median 3'-UTR lengths for the FX0 and HA0 sets are 0.935 and 0.982, respectively.