Advance notice - A communication sent to advise people that they will shortly receive a questionnaire – may be a postcard, letter, email, or phone call. Analysis - A report which includes interpretation of data in greater depth than a summary or a straight tabulation of the findings. Average - A term in statistics for a single number which is representative of a group of numbers. Although it is commonly used as a synonym for the arithmetic mean, it can also be a median or mode. Base - The number of respondents eligible to answer a specific question. Sometimes the base is adjusted to remove respondents who were eligible to answer, but didn’t (“no answers”). Before and after survey - Surveys conducted before and after a special event, such as a product launch, or sales or marketing campaign, used to measure the impact of the effort, especially in regard to awareness and impression. Bias - A systematic distortion which affects the collection, processing, analysis, and or interpretation of data. Check Box - Box used for checking off an answer on a questionnaire. Classification question - Questions designed to gather data used for classification. Closing date - The date after which no further questionnaire are tabulated as part of the survey or individual wave. Code/coding - Converting an open-ended response into a numerical code. Code booklet - A set of coding instructions outlining how to classify various responses. Competitive survey - A survey in which respondents are asked to compare competitive products or services. Consistency checking - A systematic comparison of data to eliminate logical inconsistencies. Cross tabulation - Tabulating subgroups in order to compare responses for different types of respondents. Data entry - Entering data into a computer. Data processing - The steps of combining individual data records stored on a computer into a set of tables. Demographic data - Basic descriptive data which may include, age, gender, income, and occupation. For business research, may also include items such as company sales, number of employees, and industry. Editing - Reviewing completed questionnaire to eliminate errors and inconsistencies. Extrapolating - The process of estimating unknown data based on known data. Field period - Period of time between mailing questionnaires, or launching a web survey, and the date when responses are no longer included in tabulation. Follow-up mailing - A second, third (or additional mailing to the survey sample. Typically sent only to non-respondents, and usually includes a copy of the questionnaire. Incentive - Gift, such as a $1 bill, enclosed with the questionnaire or offered in exchange for a completed survey. Making gates - A method of hand-tabulating in which the first four tabs are vertical lines and the fifth a diagonal line across them. Marginals - Straight count of survey data without crosstabs or banners. Mean - Arithmetic value derived from the sum of a set of values divided by the number of cases. Median - Arithmetic value equal to the middle value of a set of values arranged in descending or ascending order. Media Study - Study designed to measure the extent and characteristics of an audience, and the impact and awareness of publications or other media. Multiple choice question - A survey question where respondent is instructed to choose all applicable answers from a number of choices. Net mailing - The total number of questionnaires mailed minus the number returned as undeliverable. No answer - The number of respondents who did not answer a specific survey question. Non-respondent - Someone who receives a questionnaire or email invitation and does not complete the questionnaire. Numerical reply - The answer to an open-ended question which requires a number, such as age or dollar amounts. Open-ended question - Question which calls for a write-in answer. Radio Button - Used in an online survey when respondent is instructed to choose one answer from several choices. Single choice question - A survey question where respondent is instructed to choose one answer from a number of choices. Supplementary survey - Additional research conducted among a specific portion of the respondents to a prior survey.