Internal Validity In Research
Internal validity - means that the conclusion which comes from an experiment is valid for the respondents who participated in the experiment. For any experimental design, we always require interval validity, without which experimental results are not interpretable.
Threats to Internal Validity
Selection - Subjects bring with them into the investigation unique characteristics, some learned and some inherent. Examples include sex, height, weight, color, attitude, personality, motor ability, and mental ability. If assigning subjects to comparison groups results in unequal distribution of these subject-related variables, then there is a possible threat to internal validity.
History - the specific events occurring between …show more content…
Some of these changes are permanent (e.g., biological growth), while others are temporary (e.g., fatigue). Suppose that the dependent variable is measured twice for a group of subjects, once at Time A and later at Time B, and that the independent variable is introduced in the interim. If scores on the dependent measure differ at these two times, the discrepancy may be due to the independent variable or to naturally occurring developmental …show more content…
* Finally, it is much easier and more effective to show stimuli to the participants in a live setting than in an on-line focus group. While it definitely is possible to send stimuli, such as pictures or a concept statement, to participants in cyber groups, the full impact of this material is often lost in the two dimensional environment of the computer screen. The vast differences in the quality of screens and the ability of users to download the materials further exacerbate this situation. It is essential that the marketing community not become too enthralled with using the Internet to conduct qualitative research. While there may be a role for this vehicle in the very earliest stages of the process, it clearly is not a viable substitute for well-run, traditional focus groups. Online focus groups often can be accomplished faster than traditional groups because respondents are recruited from online panel members who are often qualified to match research
Threats to Internal Validity
Selection - Subjects bring with them into the investigation unique characteristics, some learned and some inherent. Examples include sex, height, weight, color, attitude, personality, motor ability, and mental ability. If assigning subjects to comparison groups results in unequal distribution of these subject-related variables, then there is a possible threat to internal validity.
History - the specific events occurring between …show more content…
Some of these changes are permanent (e.g., biological growth), while others are temporary (e.g., fatigue). Suppose that the dependent variable is measured twice for a group of subjects, once at Time A and later at Time B, and that the independent variable is introduced in the interim. If scores on the dependent measure differ at these two times, the discrepancy may be due to the independent variable or to naturally occurring developmental …show more content…
* Finally, it is much easier and more effective to show stimuli to the participants in a live setting than in an on-line focus group. While it definitely is possible to send stimuli, such as pictures or a concept statement, to participants in cyber groups, the full impact of this material is often lost in the two dimensional environment of the computer screen. The vast differences in the quality of screens and the ability of users to download the materials further exacerbate this situation. It is essential that the marketing community not become too enthralled with using the Internet to conduct qualitative research. While there may be a role for this vehicle in the very earliest stages of the process, it clearly is not a viable substitute for well-run, traditional focus groups. Online focus groups often can be accomplished faster than traditional groups because respondents are recruited from online panel members who are often qualified to match research