IBM SPSS COMPLEX SAMPLES 19 manual Sampling Wizard Sample Size

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Chapter 2

Sampling Wizard: Sample Size

Figure 2-4

Sampling Wizard, Sample Size step

This step allows you to specify the number or proportion of units to sample within the current stage. The sample size can be fixed or it can vary across strata. For the purpose of specifying sample size, clusters chosen in previous stages can be used to define strata.

Units. You can specify an exact sample size or a proportion of units to sample.

„Value. A single value is applied to all strata. If Counts is selected as the unit metric, you should enter a positive integer. If Proportions is selected, you should enter a non-negative value. Unless sampling with replacement, proportion values should also be no greater than 1.

„Unequal values for strata. Allows you to enter size values on a per-stratum basis via the Define Unequal Sizes dialog box.

„Read values from variable. Allows you to select a numeric variable that contains size values for strata.

If Proportions is selected, you have the option to set lower and upper bounds on the number of units sampled.