The
coal.ash
data frame is a spatial data set
with 208 rows and 3 columns:
x
,
y
and
coal
.
The data frame contains the following columns:
x
,
y
.
The original data were obtained from Gomez and Hazen (1970, Tables 19 and 20) for the Robena Mine Property in Greene County, Pennsylvania, USA. The data come from the Pittsburgh coal seam which is associated with a deltaic sedimentation system that includes much of southwestern Pennsylvania, northeastern Ohio and northern West Virginia. Cressie (1993) has reoriented the locations so that it appears to run in an east-west and north-south direction.
From Cressie (1993) who uses the data to illustrate kriging.
Cressie, Noel. (1993). Statistics For Spatial Data, Revised Edition. Wiley, New York.
Gomez, M. and Hazen, K. (1970). Evaluating sulfur and ash distribution in coal seams by statistical response surface regression analysis. U.S. Bureau of Mines Report RI 7377.