MARKET RESEARCH GLOSSARY - I |
Ideal Population - see Population of Interest
Identification information
Identification information lists details such as the name and address of participants in a market research project whereby they can be identified.
Implicit Alternatives
Alternatives in a question that are not expressed openly. Such alternatives may have lower chance of being selected and therefore the data may be biased.
Implicit Assumption
Implicit Assumption is when all respondents are assumed to have the same level of knowledge on a subject. Questions with implicit assumptions can lead to instrument error and/or respondent error.
Implied Population
The population as suggested by the sample, ie it is that part of the population of interest that was available for the research. When a convenience sample is used or where there is sampling frame error, the implied population could be significantly different to the population of interest (or the ideal population).
Imputed Response
A substitute for a missing response that is based on the pattern of other responses from a survey respondent.
Inability Error
Where respondents are unable to answer a particular question. This may be because they have not understood the question, they do not have the information the question requires, they cannot remember the circumstances to which the question refers or they are unable to articulate certain types of responses.
Incentive (aka Co-operation Fee or Respondent Fee)
A reward given to participants or businesses for taking the time and trouble to co-operate in a marketing research study.
Incidence (aka Strike Rate)
The proportion of respondents contacted in a survey who qualify for the survey.
In-depth Interview (aka One-on-One or Diad)
A type of qualitative research involving an unstructured personal interview with a single respondent, conducted by a highly skilled interviewer. The purpose of in-depth interviews is to understand the underlying motivations, beliefs, attitudes and feelings of respondents on a particular subject.
Index
A variable that is determined by dividing one measurement by another, and it is usually expressed as a percentage. Indices can be used to show variations over time, by comparing subsequent measurements of a variable with an initial measurement (an index of 100 indicates no change). Indices can also show the relative incidence of a particular characteristic in two samples, by dividing the percentage of one sample by the other, indices of 120 and over or 80 and below generally indicate above-average and below-average skews respectively.
Indirect Approach
An approach where the true purpose of a research project is disguised. Indirect approaches are used when revealing the true purpose of the research would bias the responses given by participants.
Indirect Observation (aka Trace Analysis)
An observation technique where some record of past behaviour is used to deduce what happened during an event, eg looking at packaging usage in a fast food restaurant to understand what flavoured drinks sell the most.
Indirect Question
A question to research participants that asks them to consider the behaviour of other people instead of their own. The purpose of indirect questions is to avoid bias caused by social group norms and the best light phenomenon.
Independent Samples
Samples that are not linked experimentally and the measurement of one sample has no effect on the others.
Independent Variable (aka Causal Variable)
A variable that exerts some influence on another (dependent) variable. Research experiments usually involve some manipulation of independent variables and measurement of dependent variables to investigate the relationship between them.
Inductive Research - see Exploratory Research
Industrial Survey
A marketing research study that focuses on products and services utilised by businesses and manufacturing firms, conducted among respondents employed in such businesses (as opposed to a consumer survey).
Initial Refusal
Initial Refusal occurs when a respondent refuses to participate in a survey at the interviewer's initial introductory statement.
Inferential Analysis
The analysis of data to test a specific hypothesis.
Information
Information involves the analysis and interpretation of data to describe something about a market.
Informed Consent
The principle that researchers should try to avoid both uninformed and misinformed participation by subjects in research.
In-Home Interview
Where participants are asked survey questions face-to-face in their own homes.
In-House Research
Research that is conducted by the staff in a client company (rather than by an agency).
In-Street Interview
Where participants are asked survey questions face-to-face in the street.
Instrument Error
A type of non-sampling error caused by the survey instrument (or questionnaire) itself, such as unclear wording, asking respondents for information they are unable to supply or the instrument being changed in some way during the course of the research.
Intended Sample
The ideal sample for a particular research project (which may be different to the resulting sample).
Interaction Effect
The effect of all the factors working together, which is greater than the sum of the separate effects.
Interactive Testing Effect - see Pre-Test Manipulation Interactive Bias
Intercept Interview (aka Mall Intercept Interview)
A type of central location interviewing where respondents are approached (or intercepted) in high traffic locations such as grocery stores or shopping malls. The main part of the interview can take place either on the mall floor or in another location (usually nearby).
Interdependence Techniques
Types of multivariate analysis techniques that are used where no distinction is made as to which variables are dependent or independent.
Interdependency
Interdependency is when variables each influence each other to some degree.
Interlocking Quotas
The numbers of interviews required with participants having several pre-defined characteristics such as age, life-cycle stage and income level.
Interquartile Range
A measure of variability and it is the range between the upper and lower quartiles (ie the middle 50% of a distribution) and it is equal to the difference between the 75th and the 25th percentile.
Internal Secondary Data
Data that have already been generated and/or collected by a business during its normal course of activity.
Internal Validity
A measure of the accuracy of an experiment in terms of the degree to which changes in the dependent variable can be attributed to manipulations of the independent variable.
ICC/ESOMAR International Code on Market and Social Research
The code of conduct of ESOMAR and sets out the rights and responsibilities of those involved in marketing and social research.
Interval Scale
A scale where equal intervals in the scale correspond to equal changes in the characteristic being measured, eg temperature scales (Celsius/Fahrenheit). Differences between objects can be analysed statistically (which is not possible with nominal or ordinal scales).
Interview
Any form of contact with a respondent in order to collect information for market research purposes.
(As defined in the ICC/ESOMAR INTERNATIONAL CODE ON MARKET AND SOCIAL RESEARCH)
Interviewer Bias - see Interviewer Error (below)
Interviewer Cheating
Interviewer Cheating is when interviewers knowingly do not follow their instructions.
Interviewer Error (aka Interviewer Bias)
A type of non-sampling error caused by mistakes made by the interviewer. These may include influencing the respondent in some way, asking questions in the wrong order, or using slightly different phrasing (or tone of voice) than other interviewers. It can include intentional errors such as cheating and fraudulent data entry.
Intra-Cultural Analysis
The breakdown of data into individual countries (or cultural units) and analysis within each individual country.
Itemised Rating Scale
A type of non-comparative scale where each choice category has some form of description (as opposed to a semantic differential scale, where only the extreme categories are labelled).
A way of ordering questions in a questionnaire where the specific questions are asked before the general questions. The approach can be useful where respondents do not have strong feelings or a general view on a subject.