HYPOTHESIS Testing

HELLO, welcome to an another blog of mine, and today i will be talking about an experiment that i have done with my group !

This time round the groupings are in random and i did the experiment where we are required to find out that what are the factors that affect the distance of the projectile flying distance. There are 3 main factors that we needed to investigate which are the start/stop angle and the length of the arm. We suspected that the arm length would be the most influential of the projectile flying distance, followed by stop and start angle.

DOE PRACTICAL TEAM MEMBERS :

1. Kittitat (Captain America)

2. Yiren (Black Widow)

3. Xavier

4. Benjamin

Roles for each character:

Iron Man will use Run #2 from FRACTIONAL factorial and Run#2 from FULL factorial.

Thor will use Run #3 from FRACTIONAL factorial and Run#3 from FULL factorial.

Captain America will use Run #5 from FRACTIONAL factorial and Run#5 from FULL factorial.

Black Widow will use Run #8 from FRACTIONAL factorial and Run#8 from FULL factorial.

Hulk will use Run #3 from FRACTIONAL factorial and Run#3 from FULL factorial.

Hawkeye will use Run #8 from FRACTIONAL factorial and Run#8 from FULL factorial.

Data collected for FRACTIONAL factorial design using CATAPULT A

Data collected for FRACTIONAL factorial design using CATAPULT B

I will use Run #5 from FRACTIONAL factorial and Run#5 from FULL factorial.

The QUESTION	The catapult (the ones that were used in the DOE practical) manufacturer needs to determine the consistency of the products they have manufactured. Therefore they want to determine whether CATAPULT A produces the same flying distance of projectile as that of CATAPULT B.
Scope of the test	The human factor is assumed to be negligible. Therefore different user will not have any effect on the flying distance of projectile.   Flying distance for catapult A and catapult B is collected using the factors below: Arm length =  33cm Start angle = 0 degree Stop angle =  90 degree
Step 1: State the statistical Hypotheses:	State the null hypothesis (H0): There is no significant increase/same in the distance of projectile when the stop angle increases  μA = μB     State the alternative hypothesis (H1): Catapult A gives different projectile flying distance from Catapult B   μA ≠ μB
Step 2: Formulate an analysis plan.	Sample size is 8<30.   Therefore t-test will be used.     Since the sign of H1 is ≠ , two 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 sample catapult A: Ave.= 110.6cm Std. Dev.= 4.97cm     State the mean and standard deviation of sample catapult B: Ave.= 107.1cm Std. Dev.= 2.16cm     Compute the value of the test statistic (t):
Step 4: Make a decision based on result	Type of test (check one only)          Two-tailed test: [ 👌 ]  Critical value tα/2 = ± 2.145   Use the t-distribution table to determine the critical value of tα or tα/2 Since t = 1.709 lies within the acceptance region of +2.145 and -2.145, Ho is accepted.
Conclusion that answer the initial question	hence, it is concluded that the products produced are consistence with one another and up to standard with slight to no significance in the projectile distance when the significance level is 0.05
Compare your conclusion with the conclusion from the other team members.   What inferences can you make from these comparisons?	the catapult A and catapult B are relatively consistent with one another hence the manufacturing process are up to standards. it can be inferred that from different stopping angle, the distance of the projectile distance are still relatively consistent with one another hence making each product have the same standards.

 

Reflection:

When I first started learning hypothesis testing, I was clueless on what to do and i do not really understand some of the things that were on the slides. I tried looking into it before the lesson started but I could not fully understand some of the content on the slides like when and how to use right/left or 2 tailed method. Moreover, after the teach had gone through the slides, I understood most of the content but the tutorials questions he gave, I could not do some of it. After he finished going through, I finally understood. Moreover, I have also learnt how to apply this in real life experiments like the one I did on the catapult.