Hypothesis Testing

HYPOTHESIS TESTING TASK FOR INDIVIDUAL BLOG

For this assignment, we will be using the DOE experimental data using the CATAPULT that we have conducted during the previous practical. 

My team members are: 

1. Yeung Juen (Iron Man)

2. Mavis (Thor) 

3. Isabelle (Captain America)

4. Alvin (Black Widow)

❓Hypothesis testing: 

It refers to the formal procedures used by experimenter or researchers to accept or reject *statistical hypotheses. 

*statistical hypothesis: an assumption about a population parameter which may or may not be true.

Data we collected for FULL FACTORIAL design using CATAPULT A:

Since I am Thor, I will be using Run #2 and #4 to determine the effect of projectile weight.

For Iron Man, Thor, Hulk. USE THIS TEMPLATE TABLE and fill all the blanks

The QUESTION	To determine the effect of _____projectile weight____ on the flying distance of the projectile
Scope of the test	The human factor is assumed to be negligible. Therefore different users will not have any effect on the flying distance of the projectile. Flying distance for catapult is collected using the factors below: Arm length =  __75__cm Projectile weight = __0.85__ grams and ___20___ grams Stop angle = ___15__ degree
Step 1: State the statistical Hypotheses:	State the null hypothesis (Ho): The projectile weight has no significant effect on the flying distance of the projectile. State the alternative hypothesis (H1): The projectile weight has a significant effect on the flying distance of the projectile.
Step 2: Formulate an analysis plan.	Sample size is __8__ Therefore t-test will be used. Since the sign of H1 is __±__, a left/two/right tailed test is used. Significance level (α) used in this test is __0.05__
Step 3: Calculate the test statistic	State the mean and standard deviation of Run # _2_: Mean = 70.9 cm Standard deviation = 1.31 State the mean and standard deviation of Run #_4_: Mean = 74.9 cm Standard deviation = 3.17 Compute the value of the test statistic (t): v= 8 + 8 - 2 = 14
Step 4: Make a decision based on result	Type of test (check one only) 1. Left-tailed test: [ __ ]  Critical value tα = - ______ 2. Right-tailed test: [ __ ]  Critical value tα =  ______ 3. Two-tailed test: [ _✔_ ]  Critical value tα/2 = ± ___2.145___   Use the t-distribution table to determine the critical value of tα or tα/2   Compare the values of test statistics, t, and critical value(s), tα or ± tα/2 tα = ± 3.085 tα/2 = ± 2.145  As seen in the graph drawn,  tα  = ± 3.085 lies in the rejected region.  Therefore Ho is ____rejected_______.
Conclusion that answer the initial question	Since Ho is rejected, H1 is accepted. This implies that the projectile weight has a significant effect on the flying distance of the projectile.
Compare your conclusion with the conclusion from the other team members.	After comparing my conclusion with my teammate YJ (iron man), both our conclusions are the same. He carried out hypothesis testing for runs #1 and 3. Ho is rejected, while H1 is accepted. which suggests that the weight of projectile has significant effect on the flying distance of the projectile.
What inferences can you make from these comparisons?	From these comparisons, projectile weight has a significant effect on the projectile's flying distance.  For my runs, the arm length was positive, which means that the longer arm is being used. On the other hand, YJ had a shorter arm length for his runs. Our results obtained were different. I got ± 3.085 while he got ± 8.605. This shows that a shorter arm length has a more significant effect on the flying distance of projectile.
Your learning reflection on this Hypothesis testing activity	This was my first time learning about hypothesis testing. Initially, I could not comprehend the calculation methods that were being taught during the tutorial session. I did not know how to read the distribution table and the symbols in the equation. I was also confused by what the different terms meant. For example, I could not differentiate between sample and population. But after reviewing the slides and seeking help from my friends, I was able to complete the practice questions myself.  From this topic, I was able to understand that hypothesis testing is a systematical method that can be used to analyze how certain factors can affect the data. I think that this skillset will definitely come into handy in the future whenever I need to carry out data analysis.