A consumer group suspects that a soft drink has higher sugar levels than what is acceptable. They hire a researcher to investigate this issue.

• Write a null and alternative hypothesis for this study
• Explain in words what a Type 1 error would mean in this situation
• Explain in words what a Type 2 error would mean in this situation

2. In a research study, you decided to change the significance level from the standard 0.05 to 0.01. Explain how this would influence:

• Type 1 error
• Type 2 error
• Power

3. You were asked to investigate the association between smoking among mothers and infant low birth weight. You were asked to calculate a measure of association like an Odds Ratio together with the confidence intervals. They asked you to calculate a 90% confidence interval instead of a 95% confidence interval.

Will the lowering of the confidence interval from 95% to 90% increase or decrease the chance of makingType 1 error? Will this affect the probability of makingType 2error? How will this affect thepowerof the study? Explain your answer.

4. Design a research project that investigates an outcome over time, with three measurements done: at baseline, 2 months, and 4 months following an intervention.

• State the research question
• Write the null and alternative hypothesis
• Discuss the effect size you will be investigating in this study
• Explain in words what a type 1 error would mean in this study
• Explain in words what a type 2 error would mean in this study