Exemples :

  • Modele Gompertz, approche lentement la saturation [ 2.19]
  • Modele Gompertz, approche la saturation à une vitesse moyenne [ 2.19_2]
  • Modele Gompertz, approche rapidement la saturation [ 2.19_3]
  • Modele Gompertz, modification de l'origine [ 2.19_4]

1.                               a=10

2.                               b=0.1

3.                               c=0.2

4.                               d=0

5.                               x<-seq(0,10,1)

6.                               y<-a*b^c^(x)+d

7.                               df<-data.frame(Effort=x, Ventes=y)

8.                               c=0.6

9.                               y<-a*b^c^(x)+d

10.                             df$Ventes2<-y

11.                             c=0.9

12.                             y<-a*b^c^(x)+d

13.                             df$Ventes3<-y

14.                             b=0.2

15.                             c=0.6

16.                             y<-a*b^c^(x)+d

17.                             df$Ventes4<-y

18.                             df

19.                             matplot(x, df[,2:5], pch = 1:4, type = "o", col = 1:4,xlab="Valeurs de x", ylab="Ventes et/ou Profits")

20.                             legend(min(x), max(df[,2:5]),names(df)[2:5], lwd=3, col=1:4, pch=1:4)

Michel Calciu calciu@iae.univ-lille1.fr; - Cours IAE de Lille 2004 - -