Encore's technology could, for example, sift through large volumes of data to indicate the most effective times for contacting people who owed money, she said.
Cooper said it could also indicate the most effective medium - such as text, phone or email - for contacting different debtors.
"It will just make us smarter at engaging with people in ways that work for them," she said.
"It's about leveraging Baycorp's data and local market expertise with Encore's industry-leading big data capabilities."
Baycorp, which has operated in New Zealand since the 1950s, has the largest customer default database in Australasia, with around $289 million in estimated remaining collections, according to a market statement from Nasdaq-listed Encore.
Baycorp New Zealand reported a $1.2 million profit from revenue of $25 million for the year to March 31, according to financial statements filed with the Companies Office.
While attracting Baycorp's notice is something most New Zealanders would rather avoid, Cooper said the firm worked hard to "treat people well" and she hoped they "walk away feeling they've had a positive experience" after having dealings with the debt collector.
The firm's services also helped New Zealand businesses - particularly small and medium-sized firms - maintain cash flow, she said.
Baycorp's existing owners, Oceania Capital Partners and SAS Trustee Capital, will retain representation on the board after Encore's investment.
The price the US firm paid for its majority stake wasn't disclosed, but ASX-listed Oceania Capital said it had sold a 27.9 per cent stake in Baycorp to Encore for A$18.3 million ($20.1 million).
Encore - which collected more than US$1.6 billion last year ($2.5 billion) - is the world's biggest debt purchaser. It acquires portfolios of consumer debt and "delinquent property tax debt" from banks, credit unions, utility providers and municipalities and employs more than 5600 staff.
