Hypothesis testing 1 Post by Day 3 your one-sample t test scenario. What would need to change in the scenario to result in the need for a two-sample t test? Explain whether the two-sample scenario would be categorized as having independent samples or related samples and discuss why. Support your post using the Learning Resources. Hypothesis testing 2 Hypothesis testing is a statistical technique through which the validity (reliability) of any statement or sample data about a population is checked (Website, 2015). For example, If we make a statement that average consumption of petrol is more in New York as compared to California. So, this is a statement that we made, and for checking the reliability of this statement, we will perform a statistical process that is called hypothesis testing. There are different ways of doing hypothesis testing. The T test is one of the two ways of doing the hypothesis testing. In t test we take one sample from the population and test the average of the population (Heiman, 2015 p. 109). For my example, \"In a school of 1000 students, A crash course was provided around 15 days back from the final exams. The company who provided the crash course claimed that every student who will attend this course will score 80% or more marks in the final exams\". Now this is a statement, which was made by the company who provided the training. How we can check the reliability of this statement? For this we will adopt the hypothesis testing, when the final results of exams will be declared. The test we will use will be a one sample t test. We will go to any class of 50 students, 25 girls and 25 boys, we will take the results of the students. Then we will perform a one sample t test. There will be 4 steps of hypothesis testing for a one sample t test. Step 1) State the hypothesis, null hypothesis and alternative hypothesis Step 2) Classify the test in to right tailed, left tailed or two tailed. This is where I am thrown off and he doesn't do the calculations... can you revise this or tell me if this is okay to post, I cant be questioned or she will know I didn't do the work. Step 3) Calculate the test statistics. Hypothesis testing 3 Step 4) Derive the conclusion by comparing t stat with test statistics value. How will we do the independent sample t test for the above same scenario? As we saw there were 50 students in class 25 boys and 25 girls. Now we will divide the one sample in to two groups or two samples. In one sample there will be results of 25 girls, and in another sample there will be results of 25 boys. Now we will make a statement that the average results of the girls are more than the boys. This is a statement. For checking the reliability of this statement we will perform the independent sample t test. The steps of testing will remain the same. There are some assumptions of an independent t test. 1) The sample comes from the normal distribution. 2) The population's standard deviation is unknown. An independent sample t test is different from a paired sample t test. The second scenario that we discussed above will be an independent sample t test and not a paired sample t test. Because in an independent sample t test we compare two different groups and in a paired sample t test, we compare two samples related to one group, containing data of different times. References Website lecture. (n.d.). Retrieved February 6, 2016, from http://forrest.psych.unc.edu/research/ vista-frames/help/lecturenotes/lecture07/definition.html Heiman, G. (2015). Behavioral sciences STAT 2 (2nd ed). Stamford, CT: Cengage.. page 109 Application: Computing t Tests The one-sample t test discussed in Chapter 6 requires that you know the population mean. It is unusual to have this information, so most studies compare two samples instead. Each sample measures a different condition of the independent variable. Before conducting a study, it is important to know if you would need to conduct a matched-samples t test or an independent-samples t test. Independent samples consist of two groups of different people. One group has been randomly selected and is not specifically tied to who is in the other group. Matched samples are groups that are deliberately selected to be similar to each other (matched pairs) or they are the same people in both groups (repeated measures). For example, you might want to select two groups that have similar heights. If height could affect the experiment, it could be best to match the groups on that variable. This Assignment will allow you to convey your understanding of the basic concepts related to t testing and will allow you to practice setting up and conducting an inferential parametric test in SPSS. Scenario: Imagine you are a researcher who believes that a relaxation technique involving visualization will help people with mild insomnia fall asleep faster. You randomly select a sample of 20 participants from a population of mild insomnia patients and randomly assign 10 to receive visualization therapy. The other 10 participants receive no treatment. You then measure how long (in minutes) it takes participants to fall asleep. Your data are below. The numbers represent the number of minutes each participant took to fall asleep. No Treatment (X1) Treatment (X2) 22 19 18 17 27 24 20 21 23 27 26 21 27 23 22 18 24 19 22 22 Assignment: To complete this Assignment, submit by Day 7 a response to each of the following: Explain whether you chose to use an independent-samples t test or a matchedsamples t test. Provide a rationale for your choice. Identify the independent and dependent variables. Knowing you believe the treatment will reduce the amount of time to fall asleep, state the null and alternate hypotheses in words (not formulas). Explain whether you would use a one-tailed or two-tailed test and why. Explain whether you have homogeneity of variance, and explain how you know. Explain why it is important to know if you have homogeneity of variance. Identify the obtained t value for this data set using SPSS. Identify the degrees of freedom and explain how you determined it. Identify the p value. Explain whether you should retain or reject the null hypothesis and why. Explain what you can conclude about the effectiveness of visualization therapy. Submit three documents for grading: your text (Word) document with your answers and explanations to the application questions, your SPSS Data file, and your SPSS Output file. Provide an APA reference list