A local restaurant wanted to test the effectiveness of its new commercial. The restaurant recruited 1,000 local residents in the district. These participants were divided into two groups. Only one group was shown the new TV commercial. Respondents were asked about their attitudes towards the restaurant in both groups.

Identify the dependent and independent variables in this experiment. What type of

design is used?

What are the potential threats to internal and external validity in this experiment? And

how can you improve it?