A sociologist wants to understand political opinions in a city. They survey only people at a college campus, where the majority tend to support one political party. What issue might affect this study?

A researcher conducts a study on sleep deprivation using only participants from one medical school. They then try to apply their findings to all adults. What limitation does this study face?

A marketing team tests two versions of an advertisement by showing each version to a different group of customers and tracking purchases. What type of research design is being used?

A scientist replicates a well-known study but gets completely different results, suggesting the original findings may not hold in all cases. Which research principle is being demonstrated?

A public health researcher studies the effects of a new exercise program on weight loss. They make sure that all participants start at similar fitness levels. What research principle is being applied?

A company surveys 500 employees about job satisfaction and finds that higher salaries correlate with higher satisfaction. However, they cannot prove that higher salaries cause satisfaction. What limitation does this study have?

A psychologist wants to test whether exposure to nature improves mood. They recruit participants and randomly assign them to either walk in a park or sit in a windowless room before taking a mood survey. What is the independent variable in this study?

A historian collects diary entries from soldiers to understand their experiences during war. They carefully analyze themes that emerge from the writings. What type of research method is being used?

A nutritionist wants to compare two diet plans. They track participants' weight loss over six months, ensuring that both groups eat the same number of calories. What research design is this?

A scientist measures the weight of a sample multiple times using the same scale and gets nearly identical results each time. However, the scale consistently shows a weight that is 2 grams heavier than the actual weight. What issue is present in this measurement process?

A researcher wants to measure students' reaction times. They use a stopwatch but notice that the recorded times vary significantly for the same action. What is lacking in this measurement process?