Reference no: EM132686193

A group of researchers conducted a study which aims to discuss the advertising effect of advertising design and the environment-protecting emotion of the graphic configuration of selfreference and argument quality, as well as their effect on advertising effect. The researchers use an experimental research method, which adopts the Between Subject Factorial Design of advertising design (with self-reference and strong arguments, with selfreference and weak arguments, with no self-reference and strong arguments, and with no selfreference and weak arguments), and environment-protecting emotion (positive and negative) is adopted, with a total of 4 experimental situations (four groups), in order to manipulate the variables and measure the advertising effect.

The formal experiment was carried out four times in the manner of collective testing. The questionnaire contents used by all the groups are the same, and only the viewed advertisements varied with the groups. At the beginning of the experiment, the research purpose was described, and then, the questionnaires were distributed.

Part 1 of the questionnaire contains the descriptions and basic information, while Part 2 contains the subject's advertising attitude test. After the subjects filled in Part 1, the testing personnel played the advertisement stimulant; after observing the advertisement stimulant, the subjects continued to fill in Part 2 of the questionnaire; lastly, they completed Part 3: the test of environment-protecting emotion. After completing the questionnaire, the testing personnel expressed their thanks by giving a little gif The authors recruited participants by open recruitment (i.e., offering any interested graduate students to participate in exchange for course credits), and then allocate the participants to the four groups (experimental situations) using randomization.

Question:

A. Explain why the use of randomization can reduce the threat to internal validity (you need to mention which threat to internal validity that randomization address and elaborate/provide argument).

B. In the experiment description above, there is only one measurement/testing carried out to measure the participants' reaction toward the advertisement stimulant. Explain the benefits of having only one test/measurement toward increasing the internal validity of the experiment.