Collecting and Handling Point Pattern Data 59
3.4.3 D ata entry checking
Initial exploration of data should include checks for errors in data entry. Typing and transcription
errors tend to produce outliers, which will be revealed by graphica l methods such as histograms a nd
boxplots of the data.
One very basic and easy step in che c king over a point pattern for data problems is to print
out the c oordinate values and mark s using as.data.frame(X) or v iew them in a spreadsheet-
like interface using View(X). Use head(as.data.frame(X)) to print only the top few lines, or
page(as.data.frame(X),method="print")to print the data a page at a time. Visually scanning
the data in this way can often reveal obvious errors in da ta entry. Errors can be cor r ...