The objective of this investigation

was to evaluate the effect of sampling on

the accuracy (precision and bias) of crop

area estimates made from classifications

of Landsat MSS data. Full-frame classifications

of wheat and non-wheat for

eighty counties in Kansas were repetitively

sampled to simulate alternative

sampling plans. Four sampling schemes

involving different numbers of samples

and different size sampling units were

evaluated. The precision of the wheat

area estimates increased as the segment

size decreased and the number of segments

was increased. Although the average

bias associated with the various sampling

schemes was not significantly different,

the maximum absolute bias was directly

related to sampling unit size.

Date of this Version