Marketing data can be found both inside, and outside of the organization. Many of the companies listed in "marketing services" will offer you tools and support in organizing and analysing the internal data (sales, customer flow, sales per customer, trends etc.). Others will offer you external data to use in your own information system, and analysis.
Generally companies in "marketing and sociological research" classification collect external data and recommend actions to companies, based on it. Their surveys vary from typically quantitive researches to qualitative ones, where the figures are more an indication rather than "precise data". The latter answer totally different questions (How and Why, and not Who, When, What, How Much).
Some of the topics you will discuss may include: retail audits, pre-tests, post-campaign evaluations, audience profile, loyalty ladder, in-depth interviews, focus groups etc.
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