TABLE 3.
Summary statistics of logistic regression model fits for prediction of the top quartile of Vibrio abundance in oysters and watera
| Sample and dependent variable | Predictor variables | K | −2log(L) | AICc | ΔAICc | AICc wt | C (%) | HL (P) |
|---|---|---|---|---|---|---|---|---|
| Oysters | ||||||||
| Elevated V. parahaemolyticus (>2.96 log MPN/g) | COPP + BWT × Bsal | 3 | 109.47 | 115.71 | 0.0 | 0.65114 | 73.7 | 0.52 |
| COPP + BWT + Bsal | 4 | 109.50 | 117.89 | 2.2 | 0.218924 | 73.4 | 0.29 | |
| COPP + BWT | 3 | 113.62 | 119.84 | 4.1 | 0.082576 | 70.7 | 0.12 | |
| COPP | 2 | 117.58 | 121.70 | 6.0 | 0.032581 | 68.6 | 0.86 | |
| BWT + Bsal | 3 | 117.37 | 123.37 | 7.7 | 0.014136 | 66.3 | 0.34 | |
| Intercept only | 1 | 127.51 | 129.55 | 13.8 | 0.000643 | |||
| Elevated V. vulnificus (>3.96 log MPN/g) | COPP + BWT + Bsal | 4 | 87.12 | 95.51 | 0.0 | 0.708921 | 86.5 | 0.44 |
| COPP + BWT | 3 | 91.28 | 97.51 | 2.0 | 0.260797 | 84.2 | 0.38 | |
| COPP + BWT × Bsal | 3 | 96.22 | 102.45 | 6.9 | 0.02206 | 82.6 | 0.37 | |
| COPP | 2 | 100.58 | 104.70 | 9.2 | 0.007162 | 81.5 | 0.65 | |
| BWT + Bsal | 3 | 102.29 | 108.52 | 13.0 | 0.001061 | 80.5 | 0.78 | |
| Intercept only | 1 | 131.48 | 133.52 | 38.0 | 3.95E−09 | |||
| Elevated tdh (>0.52 log MPN/g) | BWT + Bsal | 3 | 79.01 | 85.24 | 0 | 0.577265 | 85.2 | 0.16 |
| COPP + BWT + Bsal | 4 | 78.16 | 86.56 | 1.32 | 0.29836 | 85.7 | 0.11 | |
| COPP + BWT × Bsal | 3 | 82.08 | 88.31 | 3.07 | 0.124375 | 85.9 | 0.43 | |
| COPP + BWT | 3 | 123.20 | 129.43 | 44.19 | 1.46E−10 | 58.0 | 0.86 | |
| Intercept only | 1 | 127.51 | 129.55 | 44.31 | 1.38E−10 | |||
| COPP | 2 | 125.69 | 129.80 | 44.56 | 1.22E−10 | 56.9 | 0.72 | |
| Elevated trh (>0.40 log MPN/g) | BWT + Bsal | 3 | 63.39 | 69.62 | 0.00 | 0.514814 | 90.1 | 0.45 |
| COPP + BWT + Bsal | 4 | 62.70 | 71.10 | 1.48 | 0.245625 | 90.9 | 0.22 | |
| COPP + BWT × Bsal | 3 | 64.92 | 71.15 | 1.53 | 0.239561 | 89.0 | 0.02 | |
| COPP | 2 | 120.44 | 124.55 | 54.93 | 6.08E−13 | 61.0 | 0.32 | |
| COPP + BWT | 3 | 118.33 | 124.56 | 54.94 | 6.05E−13 | 59.9 | 0.35 | |
| Intercept only | 1 | 123.16 | 125.20 | 55.58 | 4.39E−13 | |||
| Elevated vcgC (>1.64 log MPN/g) | COPP + BWT × Bsal | 3 | 106.18 | 112.42 | 0 | 0.775304 | 74.8 | 0.67 |
| COPP + BWT + Bsal | 4 | 106.92 | 115.31 | 2.89 | 0.182775 | 74.3 | 0.76 | |
| COPP + BWT | 3 | 113.07 | 119.30 | 6.88 | 0.02486 | 69.5 | 0.45 | |
| COPP | 2 | 116.31 | 120.42 | 8.00 | 0.0142 | 69.1 | 0.38 | |
| BWT + Bsal | 3 | 117.50 | 123.73 | 11.31 | 0.002714 | 66.2 | 0.52 | |
| Intercept only | 1 | 127.51 | 129.55 | 17.13 | 0.000148 | |||
| Water | ||||||||
| Elevated V. parahaemolyticus (>1.397 log MPN/ml) | COPP + SWT + Ssal | 4 | 46.29 | 54.68 | 0.0 | 0.981729 | 96.1 | 0.63 |
| COPPTV + SWT | 3 | 56.68 | 62.91 | 8.2 | 0.016028 | 94.6 | 0.20 | |
| COPP + SWT × Ssal | 3 | 60.69 | 66.92 | 12.2 | 0.002155 | 92.2 | 0.34 | |
| COPP | 2 | 69.53 | 73.64 | 19.0 | 7.5E−05 | 91.3 | 0.12 | |
| SWT + Ssal | 3 | 70.90 | 77.12 | 22.4 | 1.32E−05 | 90.1 | 0.36 | |
| Intercept only | 1 | 125.39 | 127.42 | 72.7 | 1.57E−16 | |||
| Elevated V. vulnificus (>1.968 log MPN/ml) | COPP + SWT + Ssal | 4 | 94.71 | 103.10 | 0.0 | 0.727875 | 81.1 | 0.49 |
| COPP + SWT × Ssal | 3 | 99.67 | 105.91 | 2.8 | 0.178597 | 77.9 | 0.60 | |
| COPP + SWT | 3 | 101.38 | 107.61 | 4.5 | 0.076335 | 78.7 | 0.67 | |
| COPP | 2 | 105.52 | 110.63 | 7.5 | 0.016863 | 75.8 | 0.48 | |
| SWT + Ssal | 3 | 112.29 | 118.52 | 15.4 | 0.000326 | 68.1 | 0.45 | |
| Intercept only | 1 | 125.39 | 127.42 | 24.3 | 3.81E−06 | |||
| Elevated tdh (>0.00689 log MPN/ml) | COPP + SWT + Ssal | 4 | 72.65 | 80.96 | 0 | 0.951142 | 87.7 | 0.42 |
| SWT + Ssal | 3 | 80.77 | 87.00 | 6.05 | 0.046301 | 84.6 | 0.14 | |
| COPP + SWT | 3 | 86.67 | 92.91 | 11.96 | 0.002411 | 85.0 | 0.02 | |
| COPP + SWT × Ssal | 3 | 83.53 | 125.39 | 44.43 | 2.14E−10 | 83.4 | 0.18 | |
| COPP | 2 | 94.41 | 98.52 | 17.57 | 0.000146 | 81.6 | 0.11 | |
| Intercept only | 1 | 125.39 | 127.42 | 46.47 | 7.74E−11 | |||
| Elevated trh (>0.00389 log MPN/ml) | COPP + SWT + Ssal | 4 | 58.87 | 67.27 | 0.00 | 0.985699 | 92.7 | 0.10 |
| COPP + SWT | 3 | 70.75 | 76.98 | 9.71 | 0.007678 | 90.8 | 0.14 | |
| COPP + SWT × Ssal | 3 | 71.37 | 77.60 | 10.33 | 0.005631 | 89.5 | 0.37 | |
| SWT + Ssal | 3 | 75.20 | 81.43 | 14.16 | 0.00083 | 87.3 | <0.01 | |
| COPP | 2 | 80.59 | 84.70 | 17.43 | 0.000162 | 88.0 | 0.51 | |
| Intercept only | 1 | 125.39 | 127.42 | 60.15 | 8.55E−14 | |||
| Elevated vcgC (>0.154 log MPN/ml) | COPP + SWT × Ssal | 3 | 97.17 | 103.41 | 0 | 0.697358 | 82.0 | 0.69 |
| COPP + SWT + Ssal | 4 | 97.79 | 106.18 | 2.77 | 0.174565 | 80.9 | 0.65 | |
| SWT + Ssal | 3 | 101.05 | 107.28 | 3.87 | 0.100715 | 78.6 | 0.73 | |
| COPP | 2 | 106.61 | 110.73 | 7.32 | 0.017945 | 76.0 | 0.63 | |
| COPP + SWT | 3 | 105.79 | 112.02 | 8.61 | 0.009415 | 76.3 | 0.78 | |
| Intercept only | 1 | 127.51 | 129.55 | 26.14 | 1.47E−06 |
a
Model selection based on Akaike’s information criterion corrected for small sample size (AICc), change in AICc, and AICc weights for logistic regression models for prediction of the top quartile Vibrio abundance in oysters and water. −2log(L), two log likelihood or deviance; K, number of estimated parameters. COPP, colony overlay procedure for peptidase assay; BWT and SWT, water temperature at bottom or surface, respectively; Bsal and Ssal, salinity at bottom or surface, respectively. The concordance of logistic regression models coefficient (C) and Hosmer-Leemshow (HL) goodness-of-fit statistics are also presented.