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Table 1 Characteristics of four different base models (no predictors). Lower deviance information criterion (DIC) represents a better trade off between model fit and complexity. Models 1 and 3 have a random intercept; models 2 and 4 follow a BYM2 structure. \(D\left (\overline \theta \right)\), deviance of mean model parameters Īø; pD, effective number of parameters

From: An ecological study of socioeconomic predictors in detection of COVID-19 cases across neighborhoods in New York City

Model

Distribution

Parameters

Hyperparameters

\(D\left (\overline \theta \right)\)

pD

DIC

Model 1*

Poisson

Ī²0, Ī½i

Ļ„Ī½

1346.53

149.6

1645.73

Model 2**

Poisson

Ī²0, \(\upsilon _{i}^{*}\), \(\nu _{i}^{*}\)

Ļ„Ī³, Ļ†

1362.37

124.68

1611.73

Model 3ā€ 

Negative binomial

Ī²0, Ī½i

n, Ļ„Ī½

1855.47

3.30

1862.07

Model 4ā€”

Negative binomial

Ī²0, \(\upsilon _{i}^{*}\), \(\nu _{i}^{*}\)

n, Ļ„Ī³, Ļ†

1455.71

103.58

1662.87

  1. *Model 1: yi|Ī»iāˆ¼Pois(Ī»i), log(Ī»i)=Ī·i+log(Ei)=Ī²0+Ī½i+log(Ei)
  2. **Model 2: yi|Ī»iāˆ¼Pois(Ī»i), \(\log \left (\lambda _{i}\right)=\eta _{i}+\log \left (E_{i}\right)=\beta _{0}+\frac {1}{\sqrt {\tau _{\gamma }}}\left ({\sqrt {\varphi }\upsilon _{i}^{*}}+\sqrt {1-\varphi }\nu _{i}^{*}\right)+\log \left (E_{i}\right)\)
  3. ā€ Model 3: yi|Ī»iāˆ¼NegBin(n,Ī»i), log(Ī»i)=Ī·i+log(Ei)=Ī²0+Ī½i+log(Ei)
  4. ā€”Model 4: yi|Ī»iāˆ¼NegBin(n,Ī»i), \(\log \left (\lambda _{i}\right)=\eta _{i}+\log \left (E_{i}\right)=\beta _{0}+\frac {1}{\sqrt {\tau _{\gamma }}}\left ({\sqrt {\varphi }\upsilon _{i}^{*}}+\sqrt {1-\varphi }\nu _{i}^{*}\right)+\log \left (E_{i}\right)\)
  5. Symbols: yi, count of cases in Zip Code Tabulation Area (ZCTA) i; Ī»i, expected cases in ZCTA i; Ei, number of total COVID-19 tests in ZCTA i; Ī·i, linear predictor for ZCTA i; Ī²0, intercept; Ī½i, nonspatial random-effect; \(\nu _{i}^{*}\), scaled nonspatial random-effect; \(\upsilon _{i}^{*}\), scaled spatial random-effect with intrinsic conditional autoregressive structure; Ļ„Ī½, precision for nonspatial random effect, log-gamma prior; Ļ„Ī³, overall precision, penalized complexity (PC) prior; Ļ†, mixing parameter, PC prior; n, overdispersion parameter, PC gamma prior