Orthogonal Fractional Factorial Design - No Design Found

[acanakci]

Hello,

May I kindly ask you to elaborate on why I cannot get any design out of this syntax?

Code: Select all

Design
;alts = alt1*, alt2*
;rows = 100
;block = 20
;orth = seq
;model:
U(Alt1) = b1 * GuvenlikEkipmani[0,1] + 
          b2 * HavaDurumu[0,1] + 
          b3 * TrafikYogunlugu[0,1,2] + 
          b4 * Sigorta[0,1,2] + 
          b5 * DolaptanDolaba[0,1] + 
          b6 * CalismaSaatleri[0,1,2,3] + 
          b7 * BisikletYoluOrani[0,0.25,0.5,0.75,1] + 
          b8 * PaketBasinaMaliyet[40,80,120,160] + 
          b9 * KMBasinaMaliyet[20,30,40,50,60] + 
          i1 * GuvenlikEkipmani.dummy[1] * HavaDurumu.dummy[1] + 
          i2 * GuvenlikEkipmani.dummy[1] * BisikletYoluOrani + 
          i3 * GuvenlikEkipmani.dummy[1] * TrafikYogunlugu.dummy[1] + 
          i4 * GuvenlikEkipmani.dummy[1] * TrafikYogunlugu.dummy[2] + 
          i5 * GuvenlikEkipmani.dummy[1] * Sigorta.dummy[1] + 
          i6 * GuvenlikEkipmani.dummy[1] * Sigorta.dummy[2] + 
          i10 * BisikletYoluOrani * HavaDurumu.dummy[1] + 
          i11 * TrafikYogunlugu.dummy[1] * HavaDurumu.dummy[1] + 
          i12 * TrafikYogunlugu.dummy[2] * HavaDurumu.dummy[1] + 
          i13 * Sigorta.dummy[1] * HavaDurumu.dummy[1] + 
          i14 * Sigorta.dummy[2] * HavaDurumu.dummy[1] + 
          i16 * PaketBasinaMaliyet * HavaDurumu.dummy[1] + 
          i17 * KMBasinaMaliyet * HavaDurumu.dummy[1] + 
          i18 * BisikletYoluOrani * Sigorta.dummy[1] + 
          i19 * BisikletYoluOrani * Sigorta.dummy[2] + 
          i20 * BisikletYoluOrani * CalismaSaatleri.dummy[1] + 
          i21 * BisikletYoluOrani * CalismaSaatleri.dummy[2] + 
          i22 * BisikletYoluOrani * CalismaSaatleri.dummy[3] + 
          i23 * TrafikYogunlugu.dummy[1] * Sigorta.dummy[1] + 
          i24 * TrafikYogunlugu.dummy[1] * Sigorta.dummy[2] + 
          i25 * TrafikYogunlugu.dummy[2] * Sigorta.dummy[1] + 
          i26 * TrafikYogunlugu.dummy[2] * Sigorta.dummy[2] + 
          i33 * Sigorta.dummy[1] * CalismaSaatleri.dummy[1] + 
          i34 * Sigorta.dummy[1] * CalismaSaatleri.dummy[2] + 
          i35 * Sigorta.dummy[1] * CalismaSaatleri.dummy[3] + 
          i36 * Sigorta.dummy[2] * CalismaSaatleri.dummy[1] + 
          i37 * Sigorta.dummy[2] * CalismaSaatleri.dummy[2] + 
          i38 * Sigorta.dummy[2] * CalismaSaatleri.dummy[3] + 
          i39 * KMBasinaMaliyet * CalismaSaatleri.dummy[1] + 
          i40 * KMBasinaMaliyet * CalismaSaatleri.dummy[2] + 
          i41 * KMBasinaMaliyet * CalismaSaatleri.dummy[3] + 
          i42 * BisikletYoluOrani * TrafikYogunlugu.dummy[1] /

U(Alt2) = b1 * GuvenlikEkipmani + 
          b2 * HavaDurumu + 
          b3 * TrafikYogunlugu + 
          b4 * Sigorta + 
          b5 * DolaptanDolaba + 
          b6 * CalismaSaatleri + 
          b7 * BisikletYoluOrani + 
          b8 * PaketBasinaMaliyet + 
          b9 * KMBasinaMaliyet + 
          i1 * GuvenlikEkipmani.dummy[1] * HavaDurumu.dummy[1] + 
          i2 * GuvenlikEkipmani.dummy[1] * BisikletYoluOrani + 
          i3 * GuvenlikEkipmani.dummy[1] * TrafikYogunlugu.dummy[1] + 
          i4 * GuvenlikEkipmani.dummy[1] * TrafikYogunlugu.dummy[2] + 
          i5 * GuvenlikEkipmani.dummy[1] * Sigorta.dummy[1] + 
          i6 * GuvenlikEkipmani.dummy[1] * Sigorta.dummy[2] + 
          i10 * BisikletYoluOrani * HavaDurumu.dummy[1] + 
          i11 * TrafikYogunlugu.dummy[1] * HavaDurumu.dummy[1] + 
          i12 * TrafikYogunlugu.dummy[2] * HavaDurumu.dummy[1] + 
          i13 * Sigorta.dummy[1] * HavaDurumu.dummy[1] + 
          i14 * Sigorta.dummy[2] * HavaDurumu.dummy[1] + 
          i16 * PaketBasinaMaliyet * HavaDurumu.dummy[1] + 
          i17 * KMBasinaMaliyet * HavaDurumu.dummy[1] + 
          i18 * BisikletYoluOrani * Sigorta.dummy[1] + 
          i19 * BisikletYoluOrani * Sigorta.dummy[2] + 
          i20 * BisikletYoluOrani * CalismaSaatleri.dummy[1] + 
          i21 * BisikletYoluOrani * CalismaSaatleri.dummy[2] + 
          i22 * BisikletYoluOrani * CalismaSaatleri.dummy[3] + 
          i23 * TrafikYogunlugu.dummy[1] * Sigorta.dummy[1] + 
          i24 * TrafikYogunlugu.dummy[1] * Sigorta.dummy[2] + 
          i25 * TrafikYogunlugu.dummy[2] * Sigorta.dummy[1] + 
          i26 * TrafikYogunlugu.dummy[2] * Sigorta.dummy[2] + 
          i33 * Sigorta.dummy[1] * CalismaSaatleri.dummy[1] + 
          i34 * Sigorta.dummy[1] * CalismaSaatleri.dummy[2] + 
          i35 * Sigorta.dummy[1] * CalismaSaatleri.dummy[3] + 
          i36 * Sigorta.dummy[2] * CalismaSaatleri.dummy[1] + 
          i37 * Sigorta.dummy[2] * CalismaSaatleri.dummy[2] + 
          i38 * Sigorta.dummy[2] * CalismaSaatleri.dummy[3] + 
          i39 * KMBasinaMaliyet * CalismaSaatleri.dummy[1] + 
          i40 * KMBasinaMaliyet * CalismaSaatleri.dummy[2] + 
          i41 * KMBasinaMaliyet * CalismaSaatleri.dummy[3] + 
          i42 * BisikletYoluOrani * TrafikYogunlugu.dummy[1] $

Secondly, I wonder what default optimization algorithm is running in the examples provided in the manual with no lines as ;eff or ;alg, etc. I wanted to provide you with the example from the manual:

Code: Select all

Design
? This will generate a fractional factorial design
;alts = alt1, alt2
;rows = 12
;fact
;model:
U(alt1) = b1 + b2 * A[0,1,2] + b3 * B[0,1] /
U(alt2) = b2 * A + b4 * C[2,4,6,8]
$

Thank you,

Beyza

[Michiel Bliemer]

There does not exist an orthogonal design with the combinations of attribute levels that you have specified. Orthogonal designs are very limiting and only exist for specific combinations of numbers of levels. You are asking for a design for attributes with 2, 3, 4 and 5 levels, and such a design simply does not exist. You could change the number of levels and try again, e.g. change 5 levels into 4 levels.

A simpler solution is to use an efficient design. Replace ;orth = seq to ;eff = (mnl,d)

If no design type is specified then a random selection of choice tasks is made (there is no optimisation).

Michiel