Relationship between accuracy and number of line sampling on statistical quantity of environmental gamma ray dose rate

For the purpose to see in what accuracy the data obtained by line sampling (i.e., on the running car), represent the environmental gamma dose rate distribution, the relationship in the title was investigated using the model distribution map made from the average value (-1.3) of the power spectrum slopes derived from analysis of the dose rates. Factors were the distance, route and sampling number of observation and results were analyzed on the average, standard deviation and frequency distribution. Accuracy of the average (within 20% with the sampling number 50-100) was found to be lower (1/3) than that obtained by random sampling, of the standard deviation, lower (1/2) and of the frequency distribution, lower (80% for the 0.700 or higher correlation coefficient with sampling number 50-100 and 90% for the 0.500 or higher). With sampling number 100, estimation of the approximate accuracy was concluded to be possible. (N.I.)