COMPARISONS OF THREE WORK SAMPLING METHODS USING ALTERNATING POISSON PROCESS AS PROCESS MODEL

ABSTRACT

In order for work sampling to have predictive ability beyond the sampling period, it is necessary to have a model for the process. Alternating Poisson process (APP) has been adopted as the process model in this paper and it can be used to compare three different work sampling methods: 1) snap observation work sampling (SOWS), 2) group timing technique (GTT) and 3) continuous observation work sampling (COWS). The major contributions of this paper are primary in two ways. First, derives an approximately theoretical variance of the estimated proportion and confidence limits of the proportion by using COWS. Second, using simulation to verify that the SOWS and GTT's confidence interval estimates are not correct and cannot be used to predict the proportions of the process beyond the sampling period.

Keywords:

• work sampling
• alternating Poisson process
• snap observation work sampling
• group timing technology
• continuous observation work sampling