## Error - Modified Federov algorithm

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### Error - Modified Federov algorithm

We are trying to apply a Modified Federov algorithm for a choice experiment. Using the manual we create an excel sheet with the "candidates" and develop the following syntax:

Design
;alts = HOME, WORK, SHOPPING, LEISURE, OTHERS, FAST
;rows = 30
;block = 3
;eff=(mnl,d)
;con
;alg = mfederov(candidates=partial_design.csv)

;model:
U(HOME) = b4[2]* CI_FREE_HOME[1,-9999] + b5[0.1] * CI_POWER_HOME[3.7,11,-9999] + b6[-4.35] * CI_COST[0.2,0.4,0.6,9999] + b7[0.5] * ECO[0,1,-9999] + b9[-0.1] * WAIT_NO[0,9999]/
U(WORK) = b1[-2.12] + b4 * CI_FREE[0.6,0.8,1,-9999] + b5 * CI_POWER_WORK[3.7,11,22,-9999] + b6 * CI_COST + b7 * ECO + b9 * WAIT_NO/
U(SHOPPING) = b2[-3.37] + b4 * CI_FREE + b5* CI_POWER_SHOPPING[11,22,50,-9999] + b6 * CI_COST + b7 * ECO + b10[-0.1]* WAIT[0,20,9999] /
U(LEISURE) = b2 + b4 * CI_FREE + b5* CI_POWER_OTHERS[11,22,-9999] + b6 * CI_COST + b7 * ECO + b10 * WAIT /
U(OTHERS) = b2 + b4 * CI_FREE + b5* CI_POWER_OTHERS + b6 * CI_COST + b7 * ECO + b10 * WAIT /
U(FAST) = b2 + b4 * CI_FREE_FAST[0.8,1,-9999]+ b8[0.05] * CI_POWER_FAST[50,150,350,-9999] + b6 * CI_COST_FAST[0.4,0.6,0.8,9999] + b7 * ECO + b11[-0.1]* WAIT_FAST[5,10,20,9999]
\$

Unfortunately, we cannot run the syntax and become always the following error message (the excel sheet with the candidates is in the same folder as the syntax):

"Error: The 'candidates' parameter of the Modified Federov algorithm is neither specified as a valid number, nor a valid file name or path."

Is there something wrong with the syntax-definition of the algorithm?

Best regards
Viktoriya
Viktoriya

Posts: 5
Joined: Mon Mar 06, 2017 7:57 pm

### Re: Error - Modified Federov algorithm

Please make sure that you first load the candidateset:
File | Open | <select filename>

Then the candidate set is in memory and you can refer to it as you do without any path name.

Make sure that your CSV files has the following:
A header row, with at least the following: resp, cset, home.ci_free_home, home.ci_power_home, ... etc.
Under column resp, simply use the value 1 for each row.
Under column cset, start with 1 and increase with 1 for each candidate set row.
Under the other columns, the levels of the attributes for each alternative.

Please let me know if you still have trouble opening the candidate set.

Michiel
Michiel Bliemer

Posts: 954
Joined: Tue Mar 31, 2009 4:13 pm