Errata: Search Engines: Information Retrieval in Practice
Search Engines: Information Retrieval in Practice

Errata

Location Correction
Chapter 4, pg. 110, (PageRank, Figure 4.11) Line 14 should read "the set of pages such that"
Line 21 should read "Rq <- Rq ..." instead of "Rp <- Rq ..."
Chapter 5 (Pseudocode) Many of the pseudocode figures in Chapter 5 have been clarified. See the slides for Chapter 5 for updated versions.
Chapter 5 (Elias-Gamma codes), page 147 k_dr should be defined as
(k_d + 1) - 2^{\floor{\log_2(k_d+1)}}
Chapter 5 (Elias-Gamma codes), page 149 k_d should be defined as ceil(log k - 1). If k > 1, then the leading bit will be 1.
Chapter 5, page 150 1,2,1,6,1,2,6,11,... should be 1,2,1,6,1,3,6,11
Chapter 5, page 150 81,82,81,86,81,82,86,... should be 81,82,81,86,81,83,86,...
Chapter 5, Figure 5.17, page 168 In the bottom row the third final score should be 3:1 rather than 2:2.
Chapter 6, pg. 199 "Other studies of have" should be "Other studies have"
Chapter 7, pg. 248, (Table 7.1, Total column) (N - r_i) should be (N - n_i)
Chapter 8, pg. 317 (Table 8.4) The 40% recall column should have an average of 0.55 (rather than 0.47).
Chapter 8, pg. 317 (Figure 8.6) The 40% recall point should be at 0.55, but appears to be at 0.60.
Chapter 9, pg. 376 (Divisive clustering, Figure 9.11) Revised figure
Chapter 9, pg. 382 (K-Means) "As the algorithm proceeds, the number of clusters increases." - should be "decreases"
Chapter 10, pg. 435 (Rating with user clusters) The u variable in the correlation formula should have an overline (mean), instead of a hat.