How many times is the number of keywords in "Refuge: Part 1" episode than "Shield" episode?
"Refuge: Part 1" episode refers to title = 'Refuge: Part 1'; "Shield" episode refers to title = 'Shield'; times = divide(count(keyword where title = 'Refuge: Part 1'), count(keyword where title = 'Shield'))
SELECT CAST(SUM(CASE WHEN T1.title = 'Refuge: Part 1' THEN 1 ELSE 0 END) AS REAL) / SUM(CASE WHEN T1.title = 'Shield' THEN 1 ELSE 0 END) FROM Episode AS T1 INNER JOIN Keyword AS T2 ON T1.episode_id = T2.episode_id