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Extract posterior distributions of spatially-varying coefficients (SVCs) from a fitted ratio model with SVC specification.

Usage

svc(object, terms = NULL, summary = FALSE, probs = c(0.025, 0.5, 0.975), ...)

# S3 method for class 'ratiod_fit'
svc(object, terms = NULL, summary = FALSE, probs = c(0.025, 0.5, 0.975), ...)

# S3 method for class 'ratiod_svc_posterior'
summary(object, probs = c(0.025, 0.5, 0.975), ...)

# S3 method for class 'ratiod_svc_posterior'
print(x, ...)

# S3 method for class 'ratiod_svc_posterior'
plot(x, term = 1, type = "mean", ...)

Arguments

object

A ratiod_fit object fitted with svc argument

terms

Which SVC terms to extract. If NULL (default), extracts all.

summary

Logical; if TRUE, return summary statistics instead of full posterior draws.

probs

Quantiles to compute if summary = TRUE.

...

Ignored

x

A ratiod_svc_posterior object

term

Which term to plot (name or index). Default: first term.

type

Plot type: "mean" (default), "sd", or quantile (e.g., "q50")

Value

A ratiod_svc_posterior object containing:

  • draws: Array of posterior draws (draws x locations x terms)

  • coords: Coordinate matrix

  • term_names: Names of SVC terms

See also

spatial_svc(), plot.ratiod_svc_posterior()

Examples

# \donttest{
# Generate synthetic spatial data
set.seed(303)
n <- 30
lon <- runif(n, 0, 10)
lat <- runif(n, 0, 10)
depth <- rnorm(n)
# Spatially varying intercept w0 and depth slope w1, shared by count and
# effort
w0 <- 0.5 * sin(lon / 2) + 0.5 * cos(lat / 2)
w1 <- 0.4 * cos(lon / 3)
df <- data.frame(
  lon = lon,
  lat = lat,
  depth = depth,
  count = rpois(n, exp(3 + 0.3 * depth + w0 + w1 * depth)),
  effort = rgamma(n, shape = 4, rate = exp(-(w0 + w1 * depth)))
)

# Fit model with SVC
fit <- tratio(
  count | effort ~ depth,
  data = df,
  family = ratiod_poisson_gamma(),
  spatial = spatial_svc(~ lon + lat, terms = c(1, 2)),
  control = list(iter = 400, chains = 1, seed = 1)
)

# Extract SVC posteriors
svc_post <- svc(fit)
summary(svc_post)
#>    obs        term     coord_1     coord_2         mean        sd         q2.5
#> 1    1 (Intercept) -0.74552727 -1.33110810  0.706963299 0.1803532  0.368401333
#> 2    2 (Intercept)  1.11548899 -1.79945079  0.181872495 0.2376416 -0.246919470
#> 3    3 (Intercept)  0.31870377  1.15449865 -0.204578110 0.1878435 -0.552253873
#> 4    4 (Intercept)  0.78013618 -0.86618279 -0.089321059 0.1731485 -0.435597246
#> 5    5 (Intercept)  0.46004102 -0.73533404 -0.008096389 0.1765033 -0.369391490
#> 6    6 (Intercept)  1.63314700 -0.88217002 -0.131280205 0.1964693 -0.524130443
#> 7    7 (Intercept)  0.02631757 -0.67483168  0.306085906 0.1656406 -0.003640973
#> 8    8 (Intercept) -0.18440112 -0.09713499  0.190008502 0.1539187 -0.073689201
#> 9    9 (Intercept) -0.84498390  0.87363901  0.013839286 0.1725905 -0.404553399
#> 10  10 (Intercept) -0.85490948  1.35179725  0.079674707 0.1726053 -0.252971314
#> 11  11 (Intercept)  1.36713729  0.88483913 -0.567987780 0.2829698 -1.163473420
#> 12  12 (Intercept)  1.25035126 -0.57822590 -0.316311766 0.1698703 -0.618581993
#> 13  13 (Intercept) -1.47554201  0.58851774 -0.076998633 0.1446808 -0.353690353
#> 14  14 (Intercept) -1.71414857  0.09547305 -0.113043274 0.2186220 -0.535756023
#> 15  15 (Intercept) -1.01481202 -1.33103631  0.599314911 0.1799707  0.266097760
#> 16  16 (Intercept) -1.08795887  1.14705436  0.068952453 0.1602203 -0.204467195
#> 17  17 (Intercept) -0.39488775 -0.98385533  0.705740961 0.1744793  0.332126505
#> 18  18 (Intercept) -1.01478960 -1.23666615  0.670317731 0.2030713  0.266822081
#> 19  19 (Intercept)  0.73911051  1.16041569 -0.420391218 0.2194370 -0.836061161
#> 20  20 (Intercept)  0.47796288 -0.43555562 -0.045352663 0.1808655 -0.412287947
#> 21  21 (Intercept)  1.15784651  0.26206234 -0.763192408 0.2554864 -1.293965686
#> 22  22 (Intercept)  0.48022845  0.53267351 -0.375225578 0.1764856 -0.715820383
#> 23  23 (Intercept)  1.08986309 -0.29670057 -0.411065740 0.2057112 -0.808188337
#> 24  24 (Intercept) -0.99063147  0.81581050 -0.016039681 0.1291870 -0.260711648
#> 25  25 (Intercept)  1.09103446 -1.44834953  0.222570648 0.2074537 -0.180436197
#> 26  26 (Intercept)  0.32262042 -0.29825692 -0.055259724 0.1970254 -0.477876076
#> 27  27 (Intercept)  1.00040116  1.99477614 -0.168324457 0.2190127 -0.602675683
#> 28  28 (Intercept) -1.43188575  0.58388189 -0.096812068 0.1707463 -0.474827388
#> 29  29 (Intercept) -1.01568370  1.02552039  0.025999379 0.1359188 -0.212927145
#> 30  30 (Intercept) -0.54022902  0.52389907  0.087940474 0.2047175 -0.254191224
#> 31   1       depth -0.74552727 -1.33110810 -0.096212416 0.1848808 -0.496478386
#> 32   2       depth  1.11548899 -1.79945079 -0.324552419 0.2288978 -0.790038414
#> 33   3       depth  0.31870377  1.15449865  0.112135029 0.2396282 -0.313869018
#> 34   4       depth  0.78013618 -0.86618279 -0.334219092 0.1869990 -0.679609674
#> 35   5       depth  0.46004102 -0.73533404 -0.215645884 0.1794248 -0.521280601
#> 36   6       depth  1.63314700 -0.88217002 -0.373983901 0.1783683 -0.751273924
#> 37   7       depth  0.02631757 -0.67483168 -0.035302551 0.1703434 -0.365409151
#> 38   8       depth -0.18440112 -0.09713499  0.148213953 0.1930364 -0.133652550
#> 39   9       depth -0.84498390  0.87363901  0.270554716 0.1440466 -0.001553916
#> 40  10       depth -0.85490948  1.35179725  0.168481176 0.2439020 -0.292150725
#> 41  11       depth  1.36713729  0.88483913 -0.095955466 0.1627938 -0.385212851
#> 42  12       depth  1.25035126 -0.57822590 -0.328853155 0.1937893 -0.763958265
#> 43  13       depth -1.47554201  0.58851774  0.433700223 0.1912434  0.099744375
#> 44  14       depth -1.71414857  0.09547305  0.354357025 0.2777545 -0.079614357
#> 45  15       depth -1.01481202 -1.33103631 -0.120806742 0.2220577 -0.585678096
#> 46  16       depth -1.08795887  1.14705436  0.208907804 0.1218608 -0.012916242
#> 47  17       depth -0.39488775 -0.98385533  0.097932555 0.1947330 -0.206937798
#> 48  18       depth -1.01478960 -1.23666615 -0.111664028 0.1779871 -0.487785167
#> 49  19       depth  0.73911051  1.16041569 -0.046781931 0.1583317 -0.356282208
#> 50  20       depth  0.47796288 -0.43555562 -0.203178628 0.1552866 -0.533379140
#> 51  21       depth  1.15784651  0.26206234  0.005153748 0.2349889 -0.448638924
#> 52  22       depth  0.48022845  0.53267351  0.039745711 0.1731353 -0.340259332
#> 53  23       depth  1.08986309 -0.29670057 -0.194998636 0.1194083 -0.428340128
#> 54  24       depth -0.99063147  0.81581050  0.297942501 0.1599364 -0.032035043
#> 55  25       depth  1.09103446 -1.44834953 -0.436633602 0.2379949 -0.921435155
#> 56  26       depth  0.32262042 -0.29825692 -0.077579457 0.1433945 -0.346381492
#> 57  27       depth  1.00040116  1.99477614 -0.117108063 0.3043200 -0.811687748
#> 58  28       depth -1.43188575  0.58388189  0.436530834 0.1941419  0.091441766
#> 59  29       depth -1.01568370  1.02552039  0.253899667 0.1044769  0.055372296
#> 60  30       depth -0.54022902  0.52389907  0.285921031 0.1533128  0.022601906
#>            q50        q97.5
#> 1   0.70483682  1.103885966
#> 2   0.19242257  0.701755206
#> 3  -0.21086955  0.139889134
#> 4  -0.06933639  0.238908349
#> 5  -0.00861236  0.311793859
#> 6  -0.13046069  0.248979018
#> 7   0.30040045  0.637248759
#> 8   0.20294240  0.471073791
#> 9   0.01836104  0.343854572
#> 10  0.05322179  0.449228454
#> 11 -0.54719202  0.002991587
#> 12 -0.31969369 -0.016909143
#> 13 -0.07999497  0.205126370
#> 14 -0.12868296  0.253145219
#> 15  0.61300588  0.931267171
#> 16  0.07319716  0.383792718
#> 17  0.69040038  1.088436076
#> 18  0.68075231  1.124423609
#> 19 -0.43481042  0.062682985
#> 20 -0.05253699  0.321759915
#> 21 -0.75706811 -0.303203808
#> 22 -0.37034266 -0.044829664
#> 23 -0.39849581 -0.007657013
#> 24 -0.02062395  0.234954570
#> 25  0.23135675  0.708389090
#> 26 -0.06490811  0.319815030
#> 27 -0.15363854  0.251105227
#> 28 -0.07511114  0.164468005
#> 29  0.03471433  0.349832095
#> 30  0.07689897  0.475646104
#> 31 -0.08615237  0.255414588
#> 32 -0.31203130  0.125574171
#> 33  0.10811249  0.610014446
#> 34 -0.32795856 -0.005664490
#> 35 -0.22123324  0.160815122
#> 36 -0.35223987 -0.084612554
#> 37 -0.04281083  0.292386167
#> 38  0.11862500  0.573060246
#> 39  0.27423481  0.545650919
#> 40  0.16510722  0.652377865
#> 41 -0.09811787  0.197610633
#> 42 -0.30899897 -0.004679579
#> 43  0.44521095  0.791540573
#> 44  0.33246295  0.926193450
#> 45 -0.10770718  0.253733333
#> 46  0.20961521  0.481347033
#> 47  0.07106074  0.525481487
#> 48 -0.11381893  0.238930660
#> 49 -0.05101140  0.293546533
#> 50 -0.19170538  0.073724132
#> 51 -0.01339483  0.581441255
#> 52  0.04741741  0.362978987
#> 53 -0.18945369  0.039422226
#> 54  0.29808228  0.648200679
#> 55 -0.42372503 -0.001669192
#> 56 -0.08402612  0.215643613
#> 57 -0.08903803  0.429890910
#> 58  0.43925275  0.854412060
#> 59  0.25653403  0.463204912
#> 60  0.28481026  0.604788893
# }