Calculate the average number of repetitions in the pairs of words in which the first word id is number 34.
Pair is a relationship of two words: w1st and w2nd, where w1st is word id of the first word and w2nd is a word id of the second word; the first word id number 34 refers to w1st = 34; repetition refers to occurrences or times this pair appears; DIVIDE(SUM(occurrences where w1st = 34), COUNT(occurrences where w1st = 34));
SELECT CAST(SUM(CASE WHEN w1st = 34 THEN 1 ELSE 0 END) AS REAL) / COUNT(w1st) FROM biwords
database name:db_id language_corpus
langs table langs Cols: language id dtype integer, language dtype text, locale dtype text, pages dtype integer, words dtype integer, 
pages table pages Cols: page id dtype integer, language id dtype integer, page dtype integer, revision dtype integer, title dtype text, words dtype integer, 
words table words Cols: word id dtype integer, word dtype text, occurrences dtype integer, 
langs_words table langs_words Cols: language id dtype integer, word id dtype integer, occurrences dtype integer, 
pages_words table pages_words Cols: page id dtype integer, word id dtype integer, occurrences dtype integer, 
biwords table biwords Cols: language id dtype integer, word id of the first word dtype integer, word id of the second word dtype integer, occurrences dtype integer, 
