Table 4.
Econometric analysis details DCEs
| Item | Category | 1990–2000 | 2001–2008 | 2009–2012 | Current: 2013–2017 | ||||
|---|---|---|---|---|---|---|---|---|---|
| N = 34a | (%)b | N = 114a | (%)b | N = 179a | (%)b | N = 301a | (%)b | ||
| (a) | |||||||||
| Econometric analysis model | Random effects probit (random intercept) | 18 | (53) | 47 | (41) | 18 | (10) | 17 | (6) |
| Logit | 1 | (3) | 13 | (11) | 18 | (10) | 0 | (0) | |
| Multinomial logit | 6 | (18) | 25 | (22) | 86 | (45) | 116 | (39) | |
| Random effects logit (random intercept) | 1 | (3) | 6 | (5) | 14 | (8) | 15 | (5) | |
| Mixed logit (random parameter) | 1 | (3) | 6 | (5) | 45 | (25) | 118 | (39) | |
| Latent class | 0 | (0) | 1 | (1) | 7 | (4) | 36 | (12) | |
| Nested logit | 0 | (0) | 5 | (4) | 4 | (2) | 6 | (2) | |
| Scale-adjusted latent class | N/C | N/C | N/C | N/C | N/C | N/C | 2 | (1) | |
| Heteroskedastic multinomial logit | N/C | N/C | N/C | N/C | N/C | N/C | 11 | (4) | |
| Generalised multinomial logit | N/C | N/C | N/C | N/C | N/C | N/C | 12 | (4) | |
| Probit | 6 | (18) | 8 | (7) | 4 | (2) | 7 | (2) | |
| Other | 1 | (3) | 4 | (4) | 32 | (18) | 25 | (8) | |
| Not clearly reported | 2 | (6) | 4 | (4) | 2 | (1) | 7 | (2) | |
| (b) | |||||||||
| Software for econometric analysis | Nlogit | N/C | N/C | N/C | N/C | N/C | N/C | 65 | (22) |
| Biogeme | N/C | N/C | N/C | N/C | N/C | N/C | 5 | (2) | |
| Sawtooth | N/C | N/C | N/C | N/C | N/C | N/C | 16 | (5) | |
| R | N/C | N/C | N/C | N/C | N/C | N/C | 10 | (3) | |
| Stata | N/C | N/C | N/C | N/C | N/C | N/C | 94 | (31) | |
| SAS | N/C | N/C | N/C | N/C | N/C | N/C | 17 | (6) | |
| Other | N/C | N/C | N/C | N/C | N/C | N/C | 15 | (5) | |
| Not clearly reported | N/C | N/C | N/C | N/C | N/C | N/C | 79 | (26) | |
| Mixed logit/random parameter logit-additional information | Number of studies with additional information | N/C | N/C | N/C | N/C | 38 | (21) | 65 | (22) |
| Mean number of draws | N/C | N/C | N/C | N/C | N/C | N/C | 1354 | N/A | |
| Median number of draws | N/C | N/C | N/C | N/C | N/C | N/C | 1000 | N/A | |
| Distributional assumption: normal distribution | N/C | N/C | N/C | N/C | 20 | (52) | 53 | (18) | |
| Distributional assumption: other distribution/unclear | N/C | N/C | N/C | N/C | 19 | (50) | 12 | (4) | |
DCE discrete choice experiment, N/A not applicable, N/C not collected (data were not collected for this specific category)
aNumbers of individual studies might not add up to total Ns as some studies addressed multiple topics
bPercentages might not add up to 100% because some studies addressed multiple topics and because of rounding error