Question

Provide two different examples of how research uses hypothesis testing, and describe the criteria for rejecting the null hypothesis. Discuss why this is important in your practice and with patient interactions.

Answer 1

Answer :

Hypothesis testing :

• Making an assumption ,called hypothesis about a population parameter .
• Collecting sample data .
• Calculating a sample statistic .
• Using the sample statistic to evaluate the hypothesis

When a statistical hypothesis is tested ,there are 4 possible results :

• The hypothesis is true but our test accepts it.
• The hypothesis is false but our test rejects it.
• The hypothesis is true but our test rejects it .
• The hypothesis is false but our test accepts it.

Criteria for rejecting null hypothesis :

Set the significant level , the probability of making a type 1 error to be small - 0.01, 0.05 or 0.01 .

Compare the p value to . If the p value is less than or equal to , reject the the null hypothesis in favour of the alternate hypothesis . If the p value is greater than , do not reject the null hypothesis .

• Null hypothesis can be thought of as a nullifiable hypothesis .that means you can nullify it ,or reject it .
• What happens if you reject the null hypothesis ? It gets replaced by alternate hypothesis ,which is what you think might actually be true about a situation .
• For example let's say you think that a certain drug might be responsible for a spate of recent heart attacks.
• The drug company thinks that the drug is safe .The null hypothesis is always the accepted hypothesis ; in this example, the drug is on the market ,people are using it ,and it's generally accepted to be safe .
• Therefore ,the null hypothesis is that the drug is safe.
• The alternate hypothesis - the one you want to replace the null hypothesis ,is that the drug is not safe.
• Rejecting null hypothesis in this case means that you will have to prove that the drug is not safe .

Steps to reject the null hypothesis :

• Step 1 : state the null hypothesis . When you state the null hypothesis ,you also have to date the alternate hypothesis .sometimes it is easier to state the alternate hypothesis first ,because that's the researcher thoughts about the experiment ..
• Step 2 : if you want to reject the null hypothesis ,you can replace it by alternate hypothesis.

Importance :

Hypothesis testing is one of the most important concepts in statistics because it is how you decide if something really happened ,or if certain treatment have positive effects ,or if group differ from each other or if statistically significant and unlikely to have occurred by chance alone .in essence then , a hypothesis test is a test of significance.