Using Treatment and Control Groups to Test the Punishment Option in the Public Good Game

A researcher wants to determine if a new, higher-quality coffee bean increases customer satisfaction at a cafe. On Monday, they serve the old coffee in the usual paper cups. On Tuesday, they introduce the new, higher-quality coffee and also serve it in new, branded ceramic mugs. The researcher observes a significant increase in customer satisfaction on Tuesday and concludes that the new coffee bean was the cause. What is the primary methodological flaw in this experiment?

Evaluating a Recycling Campaign Experiment

Designing an E-commerce Experiment

An online retailer wants to determine if changing the color of their 'Buy Now' button from blue to green will increase the number of clicks it receives. Which of the following experimental designs is the most effective for establishing a clear causal link between the button color and the click rate?

Evaluating a Public Policy Experiment

A city government wants to test if installing brighter streetlights reduces crime. They select one neighborhood, install the new lights, and simultaneously increase the frequency of police patrols in that same area. After one month, crime rates in this neighborhood have dropped significantly. The government concludes that the brighter streetlights caused the reduction in crime. This conclusion is a valid inference from the described experimental setup.

An economist wants to test if a new mobile banking app feature increases how often users check their account balance. Match each element of a controlled experiment with its specific function in this study.

An economist wants to design a controlled experiment to determine if offering a small discount on a product increases the likelihood of a purchase. Arrange the following steps in the correct logical order to ensure the experiment effectively isolates the impact of the discount.

Refining an Educational Program Experiment

Evaluating a Workplace Productivity Experiment