請教一題有關game theory的作業 - 經濟

現在有兩家早餐公司

一家是 GC 另外一家競爭者是 Big Q

GC現在打算 開發or不開發 新麥片產品
Big Q 也是

GC是產業的領導者 必須決定此產品的價錢
是要aggressively(play tough) or cooperatively (play soft)

以下次firm's profits
第一個數子是 GC's profits

‧ Both firms introduce a new product and GC Corp. plays tough (0,0)
‧ Both firms introduce a new product and GC Corp. plays soft (3,3)
Only GC Corp. introduces a new product and GC Corp. plays tough (4,1)
‧ Only GC Corp. introduces a new product and GC Corp. plays soft (7,2)
‧ Only Big Q introduces a new product and GC Corp. plays tough (1,2)
‧ Only Big Q introduces a new product and GC Corp. plays soft (2,7)
‧ Neither firm introduces a new product and GC Corp. plays tough (1,1)
‧ Neither firm introduces a new product and GC Corp. plays soft (5,5)

請問要怎麼把這個問題 用Game tree畫出來呢~需要分析
要用 induction/rollback-reasoning 分析 不太懂這個意思
另外 要怎麼找 Nash equilibrium呢??

拜託了~~感謝各位

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