Reference no: EM134004181

For this assignment, you will read a few example studies and try to figure out the null and alternative hypotheses, and what the type I and type II errors would be in those situations.  No AI shortcuts — Get genuine assignment help from experienced, real tutors.

Here's an Example to give you an idea about what you'll be doing: A researcher is interested in testing whether a new therapy for adolescent depression works to reduce depression. He measures depression before and after the therapy and he expects depression levels to decrease after therapy. No AI shortcuts - Get genuine assignment help from experienced, real tutors.
Hypotheses:
Null Hypothesis: H0: depression after therapy depression before therapy (in other words, depression is the same or worse after therapy than it was before therapy);
Alternative Hypothesis: H1: depression after therapy < depression before therapy (in other words, depression is lower after therapy than it was before). This hypothesis is directional
Type I error: The researcher concludes that depression decreases after therapy, when in reality depression is the same or worse after therapy (in other words, the researcher concludes that the therapy works to reduce depression, when in reality it did not!).
Type II error: The concludes that depression levels are the same after therapy, when in reality they get better (in other words, the researcher concludes that the therapy did not work to reduce depression, when in reality it did!)

Scenario A. A researcher wants to test whether watching virtual reality (VR) nature experiences results in lower stress levels than watching standard nature videos. Participants are randomly assigned to either experience a 10-minute VR forest simulation or watch a 10-minute nature video on a regular screen. Stress is measured afterward using heart rate and self-report.
What is the null hypothesis for this scenario?
Stress after VR nature < stress after standard video
Stress after VR nature ≥ stress after standard video
Stress after VR nature ≤ stress after standard video
Stress after VR nature > stress after standard video
Stress after VR nature = stress after standard video

2-Multiple choice
What is the alternative hypothesis for scenario A?
Stress after VR nature ≤ stress after standard video
Stress after VR nature ≥ stress after standard video
Stress after VR nature = stress after standard video
Stress after VR nature > stress after standard video
Stress after VR nature < stress after standard video

3- What would be a type I error for scenario A? See the example question for guidance!

4- What would be a type II error for scenario A?

5-Multile choice

Scenario B. A researcher investigates whether improving students' sleep hygiene (e.g., consistent bedtime, no screens before bed, relaxation routine) increases cognitive performance in college students. Students are randomly assigned to follow a two-week sleep hygiene plan or maintain their normal sleep routine. After two weeks, all students complete a problem-solving test.
Is this a directional or non-directional hypothesis?