Mail Diary Panel Operations
Mail Diary Panel History
The Mail Diary Consumer Purchase and Consumption/Usage Panel has been in
continuous operation since 1969. Mail Diary Panelists maintain a diary record
of their purchases (all month) and consumption/usages, and then mail in the
diary at the end of each calendar month.
How is the Panel Structured?
The basic national panel is a sample of approximately 5000 households
originally developed in 1969 by taking a random nth name selection from a
national file of resident telephone and auto registration listings. Recruiting
is now accomplished by mail and internet (on a full "opt in" basis) and
includes a commitment on the part of all members of each household to cooperate
The panel is representative and projectable. It is proportioned to the nine U.S.
census regions, balanced on the demographic factors of age of homemaker, family
income, size of family, race and density of population, and projected to the
national household census.
How Does Mail Diary Panel Work?
Each month a printed purchase/usage diary is sent to the participating panel
family. During the month the homemaker is requested to enter into the diary,
each time the family shops, a record of products purchased and used by all
members of the family (including the spouse and children). Data typically
includes date, brand name, type or flavor as appropriate, motivation, quantity,
size, price paid, response to promotions, type of outlet, and who, when, how
often, where, how much and for what purpose the product is consumed/used.
At the end of the month the diary is mailed back to our offices. The diary sent
out for the next month's purchases serves as a reminder to mail back the
Data collection is on a monthly calendar basis for both the Purchase and the
Consumption/Usage Diaries. Project Directors review the coding and the
listings. We have developed proprietary computer programs to ensure the
validity of responses.
The form and content of the diary is an important factor in the degree of
cooperation elicited and the completeness and accuracy of the information
obtained. Mail Diary Panel's diary is an optimum working tool because we
carefully limit the number of categories surveyed each month. The most
pertinent questions are asked first, and ample space and detailed instructions
and examples are provided. Most important, each diary is custom-designed with
your input so that you can add special questions (e.g. attitude and usage) to
meet your marketing needs.
Quota sampling procedures were followed to make the panel representative of the
national household population of the country in terms of Region, Density, Age
of Homemaker, Income, Household Size and Race.
A continuing panel is a dynamic entity. To be representative of the universe,
which is constantly changing, it is necessary to conduct a continuous
recruiting program. Also we are constantly replacing panel households that
dissolve, become unresponsive, or drop out. Accordingly, a continuous
recruiting program is in operation. Normal panel turnover is 15% annually.
Sample Balancing and Projection System
Because of shifts and changes in the universe, as well as the non-response
factor in the initial or continuing panel membership, imbalances can exist
between the sample proportions and the proportions in the total population. To
adjust for these disproportionalities, the households in the sample are
assigned weights through a computer program.
The program is based on a mathematical model originally devised by Dr. W.
Edwards Deming and used by the U.S. Bureau of the Census. The program weights
and projects the sample to a number of outside characteristics. It computes the
proper weights for each cell to bring the sample into line with total
population distribution (Census data updated annually). For example, if in the
return sample the percentage of Homemakers in the age bracket 18 to 34 were
25%, and the current Census data shows the proportion in the total population
to be 30%, the sample figure is weighted up by 1.2. The program calculates the
weighting of a sample to make it agree with independent control data on six
characteristics simultaneously - Age of Homemaker, Household Income, Household
Size, Region, Density and Race. All aspects of the weighting program are in
accord with generally accepted research procedures in use throughout the
Response Rates and Incentives
Approximately 70% of the panel return the diary. A household is dropped from
the panel when it has failed to return the diary on three consecutive
occasions. To motivate and reward panelists an incentive program is provided,
based on an award point system to qualify the panelists for gifts from a
Analysis, Presentation and Reporting
MAIL DIARY PANEL'S concept is to deliver tabular data at the lowest cost
possible. Additional analyses are made available to all clients at additional
nominal charges, depending upon the size of the presentation and the frequency
of preparation. Every computer program is custom built and confidential to each
client. Charting on key measures is available on request.
The operations staff is maintained under a Director who has had twenty years'
experience in handling panel data. The Operations Department includes an
experienced editing & coding staff with individuals trained in each
category, an in-house data entry and programming staff and a complete report
generator program. These elements make possible accurate data collection and
Our clients include both large and medium sized companies. Our services are
valuable to both. Please call us for references.