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Random Digit Dialling (RDD)
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Random Digit Dialling (RDD)
National lists of telephone area codes, exchanges and individual numbers exit, make sampling for telephone interviews fairly simple.
RDD uses a computer programme to dial a random sequence of numbers (this could be a four-digits at random, which are then added to each combination of area code and telephone exchange).
RDD samples can be defined by a variety of geographies, including area code and geography. These samples will often include working, non-working and unassigned numbers, although that can be problematic, in that large numbers might be unassigned or are the wrong type of numbers (could be a business' number rather than a home number). It does however ensure each telephone number has an equal probability of selection.
RDD has a major advantage over using a telephone directory to identify sample, it includes the unlisted numbers that would be otherwise missed if the numbers were selected from a phone book or phone directory.
It is estimated that five calls must be made to get one working residential number.
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We build small, director-led, teams of sector experts who are with you from brief to debrief. As an employee-owned company, every one of us is invested in delivering quality, value, and long-term impact.
From agile testing to deep-dive strategic studies, we design research to meet your specific objectives. The agility of our in-house operations team and strength of our UK-wide recruiter network enable seamless execution at scale.
Our sector-focused teams have decades of experience understanding audiences and the complexities of the markets in which our clients operate. Working collaboratively we deliver actionable insight which drives positive change.
Contact us today to discuss your next market research project and discover how we could become a valuable extension of your team.
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Contact us today to discuss your next market research project and discover how we could become a valuable extension of your team.
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