For the Wave 14 boost (year 2) we experimented with the use of the HM Government logo on the envelopes for mailings to half of addresses. Early indications are that this has significantly increased the proportion of households where a household grid is completed, and where the household completes online. This was implemented on the boost, and so the only information we have is the address – thus the letters are addressed to “The Occupier”. It is suspected that this increases the perception that the mailing is ‘junk mail’ and so not opened. The hypothesis is that the Government logo encourages someone to open the envelope, and then read the letter.
Originally, we had considered rolling out any successful interventions on the boost to the continuing sample. However, whereas the Government logo might encourage a fresh household to open the envelope, there may be a different effect for letters addressed to a named participant. Someone who has previously participated in the survey is more likely to be aware of the Understanding Society logo, and is more likely to open an envelope addressed to them personally. Previous participants in the study will also be aware that the envelope will contain their invitation to the next wave of the study, and a gift-card. The addition of a Government logo will be new, and may potentially discourage some sample members from participating.
We experimented with the use of the Government logo on the IP mailings in IP16. Households were allocated to one of two treatment groups in equal proportions. The variable controlling allocations is in the file p_hhsamp_ip:
ff_govtlogow16 (1/2 each, allocations stratified by ff_gridmodew16 (revers coded) ff_incentw16 ff_perksw16 sampleorig)
1 = Government logo on envelope
2 = No Government logo
