Credit_card_fraud_common_merchants

// 1) match all disputed transactions
match (p:person)-[b:HAS_BOUGHT_AT {status: "Disputed"}]->(m:merchant) 
with 
collect(p) as disputer, // list of persons with disputed transactions
collect(b) as disputed, // list disputed transactions
collect(m) as merchants // list merchants with disputed transactions
// 2) match all undisputed transactions
match (p:person)-[b:HAS_BOUGHT_AT {status: "Undisputed"}]->(m:merchant)
where p in disputer // keep only transactions where the buyer is a disputer
with // group undisputed transactions by merchant
collect(p) as mUndisputer, // all persons with undisputed transactions to merchant "m"
collect(b) as mUndisputed, // all undisputed transactions to merchant "m"
m, // merchant m
disputer, disputed, merchants // pervious lists unchanged
where all(d in disputer where d in mUndisputer) // keep only merchants "m" where all disputers belong to the list of undisputers 
return disputer, disputed, mUndisputed, m, merchants