(2) Unscheduled services. When work is unscheduled, population

size must be estimated as shown at 4-630. The number of work occurrences is

determined or estimated for each billing period (usually l month) and for

the contract term (usually 12 months). It is also necessary to estimate

both the minimum and maximum population.

(f) Level of Surveillance. The level of surveillance is set at me of

two levels referred to as the normal sampling level and the minimum sampling

level in accordance with the following criteria:

(1)

Sampling level for random sampling for extrapolated deductions

(RSED).

(i) The sampling level at the inception of the contract is

the normal sampling level.

(ii) If the contractor's performance is such that the MADR is

not exceeded, surveillance may be decreased to the minimum

sampling level.

(iii) If the contractor's performance is such that the MADR

is exceeded, surveillance should be continued at the normal

sampling level.

(2)

sampling level for random sampling without extrapolated

deductions (RSWED).

(i) Initial level of sampling is the minimum sampling level.

(ii) If the contractor's performance is such that the MADR is

not exceeded, surveillance may be continued at the minimum

sampling level.

(iii) If the contractor's performance is such that the MADR

isexceeded, surveillance should be increased to the normal

sampling level.

(g) Determination of the Sample Size. Sample size requirements are

based on population size and the sampling level and are independent of the

MADR. population - sample size tables for normal sampling levels and

minimum sampling levels are in Appendix F, Table 1 and Table 2. The sample

sizes can also be determined using the RSED computer program available from

the EFDs.

When the services are unscheduled, the sample size for the normal sampling

level is initially determined on the basis of the estimated minimum monthly

population. An additional number of samples is required in anticipation of

the population exceeding the estimated minimum for the period.

Example: Determine the number of samples for routine service calls Using

the normal sampling level. Detailed calculations of minimum and maximum

populations are shown at 4.510.

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