Attribute level remains fixed despite assigning 3 levels

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Attribute level remains fixed despite assigning 3 levels

Postby izakro » Tue Aug 24, 2021 9:54 am

Dear all,
The design below has several restraints which are warranted given to nature of the problem. For some reason, the attribute NOLED.intensity receives the same level in all 18 scenarios (i.e. 20% reduction) despite the fact that it can be assigned with an additional level (i.e. no change). I was trying hard to figure out the problem with no success.
BTW, for those of you who wonder, we handled an issue of dependency between LED.esaving and LED.quality in a awkward way, knowing what we will be only able to estimate preference for LED.quality (the dependency is that If LED.quality=1 --> esavings =60% and if LED.quality=2 --> esavings=40%).
design
;alts = led*, noled*, bau*
;rows = 18
;block = 3
;eff = (mnl,d)
;alg = mfederov(candidates=3900)
;require:
bau.intensity=2
;reject:
led.quality=1 and led.cost_l>5,
led.quality=2 and led.cost_l<40,
noled.esaving_nl=20 and noled.cost_nl=150,
noled.intensity=3
;model:
U(led) = led[0]
+intensity.dummy[0.001|0.002]*intensity[2,3,1]? 1=20%reduction, 2=nochange, 3=20% increase
+quality.dummy[0.001]*quality[2,1]? 1=high glare and discomfort, 2=moderate glare & discomfort
+cost[-0.00001]*cost_l[5,40,80,120]
/
U(noled) = noled[0]
+ intensity * intensity (4-6, 4-6,4-6)
+ esaving[0.00001] * esaving_nl[20,30,40]
+ cost * cost_nl[150,200,250]
/
U(bau) = intensity * intensity
+ esaving * esaving_b[0]
+ cost * cost_b[290]

;formatTitle = 'Scenario <scenarionumber>'
;formatTableDimensions = 4, 6
;formatChoices = choice 1
;formatTable:
1,1 = 'attributes'/
1,2 = 'Light intensity'/
1,3 = 'Light glare and discomfort' /
1,4 = 'Energy savings'/
1,5 = 'Cost'/
1,6 = 'your choice'/
2,1 = 'LED'/
2,2 = '<led.intensity>' /
2,3 = '<led.quality>' /
2,4 = 'If glare is high savings =60% if glare is moderate savings=40%'/
2,5 = '<led.cost_l>' /
2,6 = '<choice 1>' /
3,1 = 'Savings without replacing streetlights' /
3,2 = '<noled.intensity>'/
3,3 = 'no change'/
3,4 = '<noled.esaving_nl>' /
3,5 = '<noled.cost_nl>' /
3,6 = '<choice 1>' /
4,1 = 'status quo'/
4,2 = 'no change'/
4,3 = 'no change'/
4,4 = '<bau.esaving_b>'/
4,5 = '<bau.cost_b>'/
4,6 = '<choice 1>'
;formatStyleSheet = Blue buttons.css
;formatAttributes:
led.intensity(1=20% reduction, 2=no change, 3= 20% increase)/
led.quality(1=high glare and discomfort, 2= moderate glare and discomfort)/
led.esaving_l(40= #%, 60= #%)/
led.cost_l(5=NIS #, 40=NIS #, 80=NIS #, 120=NIS #)/
noled.intensity(1=20% reduction, 2=no change, 3=20% increase)/
noled.esaving_nl(20= #%,30= #%, 40= #%)/
noled.cost_nl(150=NIS #, 200=NIS #, 250=NIS #)/
bau.cost_b(290=NIS #)
;formatTableStyle:
1,1 = 'default' /
1,2 = 'headingattribute' /
1,3 = 'headingattribute' /
1,4 = 'headingattribute' /
1,5 = 'headingattribute' /
1,6 = 'headingattribute' /
2,1 = 'heading1' /
2,2= 'body1' /
2,3= 'body1' /
2,4= 'body1' /
2,5= 'body1' /
2,6= 'choice1' /
3,1 = 'heading2' /
3,2= 'body2' /
3,3= 'body2' /
3,4= 'body2' /
3,5= 'body2' /
3,6= 'choice2' /
4,1 = 'heading3' /
4,2 = 'body3' /
4,3 = 'body3' /
4,4 = 'body3' /
4,5 = 'body3' /
4,6 = 'choice3'
$
izakro
 
Posts: 24
Joined: Sun Nov 08, 2020 6:11 am

Re: Attribute level remains fixed despite assigning 3 levels

Postby Michiel Bliemer » Tue Aug 24, 2021 11:06 am

This is because you have heavily constrained your attribute levels in this design, there only exist 96 feasible choice tasks. You can see them using the syntax below. Note that your dominance checks have a large impact since you only have three attributes, each with a few levels, so for Ngene to avoid dominance across the choice tasks there are not many feasible choice tasks left. Given that you seem to have a labelled experiment, I think your dominance constraints may be too strict.

Code: Select all
design
;alts = led*, noled*, bau*
;rows = all
;fact
;require:
bau.intensity=2
;reject:
led.quality=1 and led.cost_l>5,
led.quality=2 and led.cost_l<40,
noled.esaving_nl=20 and noled.cost_nl=150,
noled.intensity=3
;model:
U(led)   = led[0]
         + intensity.dummy[0.001|0.002] * intensity[2,3,1]   ? 1=20%reduction, 2=nochange, 3=20% increase
         + quality.dummy[0.001]         * quality[2,1]       ? 1=high glare and discomfort, 2=moderate glare & discomfort
         + cost[-0.00001]               * cost_l[5,40,80,120]
         /
U(noled) = noled[0]
         + intensity                    * intensity
         + esaving[0.00001]             * esaving_nl[20,30,40]
         + cost                         * cost_nl[150,200,250]
         /
U(bau)   = intensity                    * intensity
         + esaving                      * esaving_b[0]
         + cost                         * cost_b[290]
$


Michiel
Michiel Bliemer
 
Posts: 1705
Joined: Tue Mar 31, 2009 4:13 pm

Re: Attribute level remains fixed despite assigning 3 levels

Postby izakro » Wed Aug 25, 2021 4:17 am

Thank you Michiel, we will release some of the constraints.
izakro
 
Posts: 24
Joined: Sun Nov 08, 2020 6:11 am


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