OpenDP ALP

alp_queryable.py

import faker
import opendp.prelude as dp

counter = dp.t.make_count_by(
    dp.vector_domain(dp.atom_domain(T=str)),
    dp.symmetric_distance(),
    MO=dp.L1Distance[int])

alp_meas = counter >> dp.m.then_alp_queryable(
    scale=1.,
    total_limit=10_000,  # the sum of all values
    value_limit=500,     # the max of all values
)

print("ε = ", alp_meas.map(1))
# >>> ε = 1.0

# try the mechanism out on synthetic data
fake = faker.Faker()
data = [fake.first_name() for _ in range(10_000)]

alp_qbl = alp_meas(data)
# all queries sent to `alp_qbl` are post-processing

# common names have higher counts
print(alp_qbl("Michael"))
# >>> 248.0

# "Sharon" is relatively less common
print(alp_qbl("Sharon"))
# >>> 36.0

# unlikely to see any instances of Elizondeth
print(alp_qbl("Elizondeth"))
# >>> 0.0