Orthogonal Fractional Factorial Design - No Design Found

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Orthogonal Fractional Factorial Design - No Design Found

Postby acanakci » Wed Oct 16, 2024 8:25 pm

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
acanakci
 
Posts: 28
Joined: Tue Jun 11, 2024 11:55 pm

Re: Orthogonal Fractional Factorial Design - No Design Found

Postby Michiel Bliemer » Thu Oct 24, 2024 7:12 am

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
Michiel Bliemer
 
Posts: 1879
Joined: Tue Mar 31, 2009 4:13 pm


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