Model Overview

Author

Ihsan E. Buker

Ordinal Logistic Model

We are modeling \(\frac{P(Y \leq j)}{P(Y > j)} \equiv \operatorname{logit}(P(Y \leq j)); \quad j \in (1,2,3)\). The outcome is on a Likert-like scale and represents the answer to “When a safe and effective coronavirus (COVID-19) vaccine becomes available, I will get it as soon as possible (1=Strongly Disagree, 4=Strongly Agree).”

Hierarchical setup

Characteristic Model 1 Model 2 Model 3 Model 4 Model 5
OR (95% CI)1 p-value OR (95% CI)1 p-value OR (95% CI)1 p-value OR (95% CI)1 p-value OR (95% CI)1 p-value
ngender
0.083
0.13
0.046
0.14
0.015
    0




    1 1.23 (0.97, 1.57)
1.21 (0.95, 1.55)
1.29 (1.00, 1.67)
1.22 (0.93, 1.59)
1.41 (1.07, 1.85)
nmarital
>0.9
0.7
0.3
0.092
0.2
    0




    1 1.02 (0.79, 1.31)
0.94 (0.73, 1.23)
0.86 (0.65, 1.12)
0.78 (0.59, 1.04)
0.82 (0.61, 1.10)
religiosity 1.48 (1.31, 1.68) <0.001 1.45 (1.28, 1.65) <0.001 1.09 (0.95, 1.25) 0.2 1.04 (0.90, 1.20) 0.6 1.08 (0.94, 1.26) 0.3
nrace
>0.9
0.13
0.13
0.7
0.4
    0




    1 1.01 (0.78, 1.33)
0.81 (0.61, 1.07)
0.80 (0.60, 1.06)
1.06 (0.79, 1.43)
0.87 (0.64, 1.19)
nage 0.73 (0.64, 0.84) <0.001 0.77 (0.66, 0.89) <0.001 0.72 (0.62, 0.84) <0.001 0.77 (0.65, 0.90) 0.001 0.70 (0.59, 0.83) <0.001
nincome 0.91 (0.86, 0.97) 0.002 0.92 (0.86, 0.98) 0.006 0.95 (0.89, 1.02) 0.14 0.97 (0.91, 1.04) 0.3 0.94 (0.88, 1.01) 0.093
nemploy
<0.001
<0.001
0.003
0.016
0.041
    0




    1 1.82 (1.39, 2.39)
1.70 (1.29, 2.25)
1.53 (1.15, 2.04)
1.44 (1.07, 1.93)
1.37 (1.01, 1.86)
neduc 0.53 (0.46, 0.61) <0.001 0.57 (0.49, 0.66) <0.001 0.66 (0.57, 0.77) <0.001 0.71 (0.61, 0.83) <0.001 0.67 (0.57, 0.79) <0.001
onlinesocialnews

0.99 (0.95, 1.04) 0.7 0.97 (0.93, 1.02) 0.2 0.96 (0.92, 1.01) 0.14 1.00 (0.95, 1.05) >0.9
natnewspaper

0.79 (0.73, 0.86) <0.001 0.88 (0.81, 0.96) 0.003 0.91 (0.83, 1.00) 0.047 0.93 (0.84, 1.02) 0.11
nattvnews

0.86 (0.79, 0.95) 0.002 0.93 (0.85, 1.02) 0.14 0.94 (0.85, 1.04) 0.2 0.99 (0.89, 1.10) 0.9
locnewspaper

1.06 (0.98, 1.15) 0.13 1.06 (0.98, 1.15) 0.2 1.06 (0.98, 1.16) 0.15 1.07 (0.98, 1.17) 0.11
loctvnews

0.96 (0.87, 1.06) 0.4 0.94 (0.86, 1.04) 0.3 0.94 (0.85, 1.04) 0.3 0.98 (0.88, 1.09) 0.7
chipcovid



2.44 (2.04, 2.93) <0.001 1.62 (1.34, 1.98) <0.001 1.51 (1.24, 1.85) <0.001
politview



1.42 (1.29, 1.56) <0.001 1.38 (1.25, 1.53) <0.001 1.25 (1.13, 1.39) <0.001
safetyvac





2.29 (1.91, 2.75) <0.001 2.52 (2.09, 3.05) <0.001
sideeffect





1.72 (1.41, 2.10) <0.001 1.77 (1.44, 2.19) <0.001
effectivevac





0.41 (0.32, 0.53) <0.001 0.57 (0.43, 0.76) <0.001
worrycovid







0.97 (0.94, 0.99) <0.001
fearlovedcovid







0.57 (0.49, 0.66) <0.001
familyhealth







0.88 (0.69, 1.12) 0.3
communhealth







0.62 (0.49, 0.77) <0.001
1 OR = Odds Ratio

Single-stage setup

Characteristic OR (95% CI)1 p-value
worrycovid 0.97 (0.94, 0.99) <0.001
fearlovedcovid 0.57 (0.49, 0.66) <0.001
familyhealth 0.88 (0.69, 1.12) 0.3
communhealth 0.62 (0.49, 0.77) <0.001
safetyvac 2.52 (2.09, 3.05) <0.001
sideeffect 1.77 (1.44, 2.19) <0.001
effectivevac 0.57 (0.43, 0.76) <0.001
chipcovid 1.51 (1.24, 1.85) <0.001
politview 1.25 (1.13, 1.39) <0.001
onlinesocialnews 1.00 (0.95, 1.05) >0.9
natnewspaper 0.93 (0.84, 1.02) 0.11
nattvnews 0.99 (0.89, 1.10) 0.9
locnewspaper 1.07 (0.98, 1.17) 0.11
loctvnews 0.98 (0.88, 1.09) 0.7
ngender
0.015
    0
    1 1.41 (1.07, 1.85)
nmarital
0.2
    0
    1 0.82 (0.61, 1.10)
religiosity 1.08 (0.94, 1.26) 0.3
nrace
0.4
    0
    1 0.87 (0.64, 1.19)
nage 0.70 (0.59, 0.83) <0.001
nincome 0.94 (0.88, 1.01) 0.093
nemploy
0.041
    0
    1 1.37 (1.01, 1.86)
neduc 0.67 (0.57, 0.79) <0.001
1 OR = Odds Ratio

Bayesian Monotonic Regression

The effect of the linear predictor on the outcome is expressed as

\[ \eta_n = b \cdot D \sum_{i \in x_n} \zeta_i \]

Where \(b\) is the size and direction of the monotonic effect, \(D\) is the number of categories in \(x_n\) minus one (i.e., same as \(\operatorname{dom}(i)\)), and \(\zeta_i \in [0,1]\) is a simplex that scales \(b\) between levels of \(x_n\). The upcoming model was fit using non-informative priors, four chains with 4,000 iterations each, where the first half of the samples from each chain were discarded.

For comparison sake, a non-monotonic ordinal regression model was fit using the similar non-informative priors and sampler settings. Both the Bayes Factor and the LOO-CV approach found the monotonic effects model to be superior to the non-monotonic effects model in the Bayesian framework.

 Family: cumulative 
  Links: mu = logit; disc = identity 
Formula: ordered(Covidhesit) ~ worrycovid + ngender + nmarital + nrace + nemploy + nregion + mo(fearlovedcovid) + mo(familyhealth) + mo(communhealth) + mo(safetyvac) + mo(sideeffect) + mo(effectivevac) + mo(chipcovid) + mo(politview) + mo(onlinesocialnews) + mo(natnewspaper) + mo(nattvnews) + mo(locnewspaper) + mo(loctvnews) + mo(religiosity) + mo(nage) + mo(nincome) + mo(neduc) 
   Data: chapman_21_cont (Number of observations: 991) 
  Draws: 4 chains, each with iter = 2000; warmup = 1000; thin = 1;
         total post-warmup draws = 4000

Regression Coefficients:
                   Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS Tail_ESS
Intercept[1]          -3.70      0.73    -5.22    -2.37 1.00     2187     2543
Intercept[2]          -1.60      0.73    -3.10    -0.25 1.00     2227     2415
Intercept[3]           0.56      0.71    -0.88     1.86 1.00     2315     2523
worrycovid            -0.04      0.01    -0.06    -0.02 1.00     4133     2787
ngender1               0.29      0.14     0.00     0.57 1.00     4208     2898
nmarital1             -0.30      0.15    -0.61    -0.02 1.00     3542     2650
nrace1                -0.18      0.16    -0.51     0.15 1.00     2757     2711
nemploy1               0.17      0.17    -0.16     0.50 1.00     2988     2986
nregion2               0.22      0.21    -0.20     0.64 1.00     2905     2863
nregion3               0.08      0.19    -0.29     0.45 1.00     2576     2737
nregion4              -0.32      0.21    -0.73     0.11 1.00     2729     2922
mofearlovedcovid      -0.67      0.09    -0.85    -0.50 1.00     3647     3211
mofamilyhealth        -0.17      0.13    -0.44     0.07 1.00     2724     2894
mocommunhealth        -0.44      0.14    -0.75    -0.21 1.00     2539     2335
mosafetyvac            0.90      0.11     0.69     1.11 1.00     2881     3339
mosideeffect           0.52      0.14     0.29     0.83 1.00     2048     2481
moeffectivevac        -0.55      0.21    -1.03    -0.21 1.00     2134     1993
mochipcovid            0.34      0.10     0.16     0.54 1.00     3339     2791
mopolitview            0.29      0.08     0.15     0.45 1.00     2401     2970
moonlinesocialnews    -0.00      0.03    -0.06     0.05 1.00     3632     2853
monatnewspaper        -0.09      0.06    -0.20     0.02 1.00     3010     3101
monattvnews           -0.01      0.06    -0.12     0.11 1.00     2498     2965
molocnewspaper         0.07      0.04    -0.02     0.16 1.00     2884     2894
moloctvnews           -0.02      0.06    -0.13     0.09 1.00     2589     2873
moreligiosity          0.10      0.09    -0.08     0.26 1.00     2474     3060
monage                -0.36      0.08    -0.52    -0.20 1.00     2588     2736
monincome             -0.05      0.04    -0.13     0.01 1.00     2519     2752
moneduc               -0.39      0.11    -0.63    -0.19 1.00     2205     2922

Monotonic Simplex Parameters:
                        Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS
mofearlovedcovid1[1]        0.54      0.08     0.38     0.69 1.00     3594
mofearlovedcovid1[2]        0.12      0.07     0.01     0.29 1.00     2622
mofearlovedcovid1[3]        0.34      0.08     0.18     0.49 1.00     5539
mofamilyhealth1[1]          0.36      0.23     0.02     0.85 1.00     3765
mofamilyhealth1[2]          0.32      0.22     0.02     0.81 1.00     3976
mofamilyhealth1[3]          0.32      0.21     0.01     0.80 1.00     4135
mocommunhealth1[1]          0.37      0.18     0.03     0.69 1.00     2641
mocommunhealth1[2]          0.12      0.10     0.00     0.39 1.00     2820
mocommunhealth1[3]          0.51      0.17     0.24     0.87 1.00     2826
mosafetyvac1[1]             0.22      0.08     0.06     0.37 1.00     2767
mosafetyvac1[2]             0.33      0.07     0.21     0.48 1.00     2931
mosafetyvac1[3]             0.44      0.07     0.31     0.58 1.00     4485
mosideeffect1[1]            0.30      0.16     0.02     0.60 1.00     1684
mosideeffect1[2]            0.14      0.10     0.01     0.37 1.00     2514
mosideeffect1[3]            0.56      0.15     0.31     0.86 1.00     2414
moeffectivevac1[1]          0.34      0.20     0.03     0.73 1.00     2223
moeffectivevac1[2]          0.34      0.19     0.03     0.72 1.00     3167
moeffectivevac1[3]          0.31      0.16     0.07     0.70 1.00     2961
mochipcovid1[1]             0.46      0.17     0.16     0.83 1.00     2610
mochipcovid1[2]             0.39      0.17     0.04     0.72 1.00     3194
mochipcovid1[3]             0.15      0.12     0.01     0.43 1.00     3311
mopolitview1[1]             0.17      0.11     0.01     0.41 1.00     3200
mopolitview1[2]             0.22      0.11     0.03     0.47 1.00     2434
mopolitview1[3]             0.09      0.08     0.00     0.28 1.00     2530
mopolitview1[4]             0.10      0.08     0.00     0.30 1.00     3315
mopolitview1[5]             0.16      0.10     0.01     0.39 1.00     3668
mopolitview1[6]             0.26      0.14     0.02     0.54 1.00     2801
moonlinesocialnews1[1]      0.11      0.09     0.00     0.35 1.00     3763
moonlinesocialnews1[2]      0.10      0.09     0.00     0.34 1.00     3904
moonlinesocialnews1[3]      0.10      0.09     0.00     0.33 1.00     3466
moonlinesocialnews1[4]      0.10      0.09     0.00     0.33 1.00     4276
moonlinesocialnews1[5]      0.10      0.09     0.00     0.32 1.00     3898
moonlinesocialnews1[6]      0.10      0.09     0.00     0.33 1.00     3157
moonlinesocialnews1[7]      0.10      0.09     0.00     0.33 1.00     4092
moonlinesocialnews1[8]      0.10      0.09     0.00     0.32 1.00     4584
moonlinesocialnews1[9]      0.10      0.09     0.00     0.33 1.00     3721
moonlinesocialnews1[10]     0.11      0.09     0.00     0.35 1.00     4627
monatnewspaper1[1]          0.14      0.13     0.00     0.47 1.00     2829
monatnewspaper1[2]          0.18      0.15     0.01     0.57 1.00     3043
monatnewspaper1[3]          0.14      0.13     0.00     0.50 1.00     3864
monatnewspaper1[4]          0.21      0.16     0.01     0.61 1.00     3876
monatnewspaper1[5]          0.33      0.21     0.02     0.75 1.00     2792
monattvnews1[1]             0.20      0.18     0.00     0.64 1.00     2784
monattvnews1[2]             0.20      0.16     0.01     0.61 1.00     3843
monattvnews1[3]             0.20      0.17     0.01     0.61 1.00     3603
monattvnews1[4]             0.19      0.16     0.01     0.59 1.00     4565
monattvnews1[5]             0.21      0.17     0.01     0.61 1.00     4045
molocnewspaper1[1]          0.25      0.18     0.01     0.64 1.00     3058
molocnewspaper1[2]          0.19      0.16     0.01     0.59 1.00     3723
molocnewspaper1[3]          0.16      0.14     0.00     0.52 1.00     3417
molocnewspaper1[4]          0.24      0.18     0.01     0.65 1.00     3523
molocnewspaper1[5]          0.16      0.14     0.00     0.52 1.00     4591
moloctvnews1[1]             0.21      0.17     0.01     0.61 1.00     3619
moloctvnews1[2]             0.18      0.15     0.01     0.56 1.00     2973
moloctvnews1[3]             0.20      0.16     0.01     0.59 1.00     3772
moloctvnews1[4]             0.19      0.16     0.01     0.58 1.00     3605
moloctvnews1[5]             0.22      0.17     0.01     0.61 1.00     3792
moreligiosity1[1]           0.24      0.20     0.01     0.76 1.00     2986
moreligiosity1[2]           0.24      0.20     0.01     0.75 1.00     3306
moreligiosity1[3]           0.52      0.25     0.03     0.92 1.00     2350
monage1[1]                  0.06      0.06     0.00     0.22 1.00     3267
monage1[2]                  0.53      0.15     0.23     0.85 1.00     3342
monage1[3]                  0.40      0.16     0.09     0.71 1.00     3094
monincome1[1]               0.13      0.11     0.00     0.41 1.00     2876
monincome1[2]               0.13      0.11     0.00     0.40 1.00     3720
monincome1[3]               0.10      0.09     0.00     0.33 1.00     3738
monincome1[4]               0.10      0.09     0.00     0.35 1.00     4439
monincome1[5]               0.12      0.11     0.00     0.39 1.00     4123
monincome1[6]               0.15      0.12     0.00     0.45 1.00     2843
monincome1[7]               0.13      0.11     0.00     0.43 1.00     3978
monincome1[8]               0.13      0.12     0.00     0.42 1.00     3761
moneduc1[1]                 0.34      0.17     0.03     0.67 1.00     2353
moneduc1[2]                 0.31      0.16     0.04     0.67 1.00     2833
moneduc1[3]                 0.34      0.15     0.07     0.68 1.00     3654
                        Tail_ESS
mofearlovedcovid1[1]        2466
mofearlovedcovid1[2]        1740
mofearlovedcovid1[3]        2951
mofamilyhealth1[1]          1960
mofamilyhealth1[2]          2940
mofamilyhealth1[3]          2583
mocommunhealth1[1]          2260
mocommunhealth1[2]          1954
mocommunhealth1[3]          2651
mosafetyvac1[1]             1472
mosafetyvac1[2]             2712
mosafetyvac1[3]             3251
mosideeffect1[1]            1438
mosideeffect1[2]            1566
mosideeffect1[3]            2652
moeffectivevac1[1]          1940
moeffectivevac1[2]          1919
moeffectivevac1[3]          2221
mochipcovid1[1]             1907
mochipcovid1[2]             1904
mochipcovid1[3]             2208
mopolitview1[1]             2156
mopolitview1[2]             1332
mopolitview1[3]             1511
mopolitview1[4]             1827
mopolitview1[5]             2060
mopolitview1[6]             2146
moonlinesocialnews1[1]      1969
moonlinesocialnews1[2]      1971
moonlinesocialnews1[3]      2046
moonlinesocialnews1[4]      1880
moonlinesocialnews1[5]      2265
moonlinesocialnews1[6]      1805
moonlinesocialnews1[7]      2394
moonlinesocialnews1[8]      2766
moonlinesocialnews1[9]      2576
moonlinesocialnews1[10]     2599
monatnewspaper1[1]          1857
monatnewspaper1[2]          1632
monatnewspaper1[3]          2153
monatnewspaper1[4]          2321
monatnewspaper1[5]          2699
monattvnews1[1]             1683
monattvnews1[2]             1974
monattvnews1[3]             2282
monattvnews1[4]             2809
monattvnews1[5]             3005
molocnewspaper1[1]          1567
molocnewspaper1[2]          2123
molocnewspaper1[3]          1828
molocnewspaper1[4]          2687
molocnewspaper1[5]          2795
moloctvnews1[1]             1740
moloctvnews1[2]             2070
moloctvnews1[3]             2246
moloctvnews1[4]             1973
moloctvnews1[5]             2487
moreligiosity1[1]           2019
moreligiosity1[2]           2251
moreligiosity1[3]           2602
monage1[1]                  1537
monage1[2]                  2119
monage1[3]                  1776
monincome1[1]               1470
monincome1[2]               2064
monincome1[3]               2099
monincome1[4]               2331
monincome1[5]               1921
monincome1[6]               1562
monincome1[7]               2550
monincome1[8]               2285
moneduc1[1]                 1931
moneduc1[2]                 2155
moneduc1[3]                 2267

Further Distributional Parameters:
     Estimate Est.Error l-95% CI u-95% CI Rhat Bulk_ESS Tail_ESS
disc     1.00      0.00     1.00     1.00   NA       NA       NA

Draws were sampled using sampling(NUTS). For each parameter, Bulk_ESS
and Tail_ESS are effective sample size measures, and Rhat is the potential
scale reduction factor on split chains (at convergence, Rhat = 1).
Iteration: 1
Iteration: 2
Iteration: 3
Iteration: 4
Iteration: 5
Iteration: 6
Iteration: 7
Iteration: 1
Iteration: 2
Iteration: 3
Iteration: 4
Iteration: 5
Iteration: 6