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stratified_sampling

stratified_sampling is a child class of Sampler class. It randomly samples alternatives from choice population according to their stratum setting. Its run method accepts the following arguments:

dataset1
- an instance of Dataset, to be used as agent set.
dataset2
- an instance of Dataset, to be used as choice set.
index1
- indices of dataset1 for whom alternatives are sampled. If it is not given, all elements of dataset1 are used.
index2
- indices of dataset2 from which alternatives are sampled. If it is not given, all elements of dataset2 are used.
stratum
- an array indicates the stratum id for elements of dataset2; it has to be either of None, or of the same size as index2 or dataset2. If it's not given, all elements are treated as in 1 stratum.
weight
- like in weighted_sampling, weight is an array used as weight for elements of dataset2 in unequal probability sampling; it has to be either of None, or of the same size as index2 or dataset2. If it is not given, sampling is proceeded with equal probability.
sample_size
- number of alternatives sampled from one stratum; default value is 1.
sample_size_from_chosen_stratum
- number of alternatives sampled from agent's chosen stratum. If it's None, it's equal to value specified by sample_size or sample|_rate.
sample_rate
- calculate number of alternatives sampled from one stratum by multiplying this rate with number of observations in this stratum. If both sample_rate and sample_size are specified, use sample_rate.
include_chosen_choice
- whether agents' chosen choice will be included in the return results. If it's true, the chosen choices are in the first column of the return results.
resources
- an instance of Resources that can be used to pass any of the above arguments to run method.


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Next: Specification and Coefficients Up: Sampler Class Previous: weighted_sampling   Index
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