diff --git a/R/data.R b/R/data.R
index 18a4242b..b504a941 100644
--- a/R/data.R
+++ b/R/data.R
@@ -35,3 +35,11 @@
 #' @docType data
 #' @keywords dataset srs_table
 "srs_table"
+
+#' @title example of spatial information system spatial adjacency matrix
+#'
+#' @name ssr_wt
+#' @format \code{ssr_wt}: A matrix with 11rows and 11cols.
+#' @docType data
+#' @keywords dataset ssr_wt
+"ssr_wt"
diff --git a/data/ssr_wt.rda b/data/ssr_wt.rda
new file mode 100644
index 00000000..30568a60
Binary files /dev/null and b/data/ssr_wt.rda differ