Part B, Attachment A - Contact Frame

Supporting Statement B, Attachment A: Use of the Census Bureau’s Contact Frame for the Household Pulse Survey

Since 2013, the Census Bureau has maintained contact frames to allow us to append contact information onto sample units within household sample frames, to aid in contacting respondents at those households. Primary motivation for creating this contact frame was to support research on potential contact strategies for the 2020 Census.

Composition

• This information is maintained in two separate files – one containing phone numbers (both landline and cell phones) and the other containing email addresses.

• Information is obtained primarily from commercial sources, with additions from respondents to the American Community Survey and Census tests, as well as participants in SNAP/TANF/WIC programs from a few states, as well as from the Alaska Permanent Fund Division.

• Commercial sources were evaluated against respondent reported phone numbers to determine which sources would be acquired, after determining which vendors provided the best value for the government.

• Commercial, survey, and administrative record data providers link phone numbers and email addresses to physical addresses before providing them for the Contact Frame.

• Addresses are matched to our Master Address File (MAF). For addresses matched with confidence, the contact information is added to the frame along with the unique identifier from the MAF.

Coverage

• The phone frame contains over a billion phone/address pairs, and the email frame contains over 686 million well-formed email/address pairs.

• The phone frame contains phone/address pairs for over 88% of addresses in the country, and over three quarters of those phones were acquired in the past two years.

• The email frame contains email/address links for almost 80% of addresses in the country, and two thirds of those emails were acquired in past two years.

Modeling

• If more than one phone is associated with an address, we score each address/phone link (and do similarly for each email address).

• In order to identify which phone or email is most likely to be correctly associated with an address, we developed a logistical model that considers characteristics of the source(s) of the data, some household characteristics, phone type, and indicators that the contact information once associated with one address is now linked to a different address.