In: Statistics and Probability
Statistical hypotheses. State the appropriate (1) statistical test, (2) experimental design (where appropriate) and (3) statistical null hypothesis for the following (set a=0.05 and assume normality unless otherwise stated).
1. Research question: Is the mean amount of exposure to microwave radiation less than 10 microwatts/cm2?
Test:
Ho: H1:
2. Research question: Is the mean amount of exposure to microwave radiation differ from the DOE specified exposure threshold of 15 mw/cm2 ?
Ho: H1:
3. Blood CO2 tension (mm Hg) was measured in patients with chronic hypercapnic respiratory failure before and after a weight loss program. Research question: Does the weight loss program affect CO2 tension?
Experimental design: Test:
Ho: H1:
4. Urinary excretion of 5-HIAA (mg/24 hrs) was compared in two groups of individuals: those with carcinoid heart disease and those without disease. You suspect that that the distribution of at least one sample is not normally distributed. Research question: Does 5-HIAA excretion differ between the groups?
Test:
Ho: H1:
5. Blood temperature of the brachial artery is measured as it enters the flipper of a porpoise and again as it exits the flipper in the brachial vein. Twenty-four total blood temperature readings were obtained from twelve porpoises. Research question: Does arterial blood temp. greater than that of venous blood temperature?
Experimental design: Test:
Ho: H1:
6. Perceived exertion levels are ranked for a group of couch potatoes while resting and then again after running on a treadmill. Research question: Does perceived exertion differ between the before and after measurements?
Experimental design: Test:
Ho: H1:
7. To determine the effectiveness of a new blood pressure drug, 10 individuals receive the drug and 10 people get a placebo. Individuals of similar age and hypertension were assigned one to each treatment. Does the new drug have an effect?
Experimental design: Test:
Ho: H1:
8. Beagles with chronic hyperactivity were randomly placed into two groups; one group received Coma-calm (doggie Prozac) and the other group a placebo. Activity levels of the two groups were ranked 2-hours after administration. Research question: Is Coma-calm effective in reducing hyperactivity levels?
Scale of measurement: Test:
Ho: H1:
9. For the following hypotheses and sample sizes, determine the critical value with which the test statistic is compared:
(1)
H0: Mean amount of exposure to microwave radiation greater than and equal to 10 microwatts/cm2
H1: Mean amount of exposure to microwave radiation less than 10 microwatts/cm2
(2)
Is the mean amount of exposure to microwave radiation differ from the DOE specified exposure threshold of 15 mw/cm2 ?
H0: Mean amount of exposure to microwave radiation does not differ from the DOE specified exposure threshold of 15 mw/cm2
H1: Mean amount of exposure to microwave radiation differ from the DOE specified exposure threshold of 15 mw/cm2
(3)
H0: The weight loss program does not affect CO2 tension
H1: The weight loss program affect CO2 tension
(4)
H0: 5-HIAA excretion doesn't differ between the groups
H1: 5-HIAA excretion differ between the groups
(5)
H0: Arterial blood temp. smaller than and equal to that of venous blood temperature
H1: Arterial blood temp. greater than that of venous blood temperature
(6)
H0: perceived exertion doesn't differ between the before and after measurements
H1: perceived exertion differ between the before and after measurements
(7)
H0: the new drug doesn't have an effect
H1: the new drug have an effect
(8)
H0: Coma-calm effective in not reducing hyperactivity levels
H1: Coma-calm effective in reducing hyperactivity levels