saddle.
• If q ∈
1 2 -1
1σ
2-α (1 -1 ) ’ 2-α (1 -1 )
, then 1-σ [1 — q(2 — a + α)] > 1 and, therefore, ∖trJ| <
11 + DetJ|. If ∖DetJ| > 1, the steady state is unstable. If ∖DetJ| < 1, the steady
state is a sink.
When σ < 1, there are two cases:
• If σ < 2 ,it can be shown that 0 < ^-^ [1 — qr(2 — a + α )] < 1 and, therefore,
[trJ| < 11 + DetJ|.If ]DetJ| > 1, the steady state is unstable. If ]DetJ| < 1, the
steady state is a sink.
• If 1 > σ > 2, there are two subcases depending on ρ:
, „ 2-1 , _ r . , . , , „ , ,, , . _ ,,
a/ If q < -—, σ 1., then τσ~ [1 — q(2 — α + α)] > 1 and, therefore, [trJ| > 11 + DetJ|.
' 2—α (1 — σ ) 1σl- v^ σ',j 1 11 1
The steady state is a saddle.
2_ 1
b/ If q > -—, σ 1., then τσ~ [1 — q(2 — a + α)] < 1 and, therefore, [trJ| < 11 + DetJ|.
' 2α (1 σ ) 1σl- σ',j
If ]DetJ| > 1, the steady state is unstable. If ]DetJ| < 1, the steady state is a sink.
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