Standard Deviation + T test

Question 1

What is it

Answer 1

Standard deviation
-how spread out the data are from the mean

T test
-is the difference in value of mean between different results are statistically significant

Question 2

Standard deviation

Answer 2

1)value of data from a result collected - mean
2)square it
3)do it for all result in that category
4)n = sets of data collected
5)n-1
6)divide value of step 3 with n-1
7)square root it for standard deviation

Question 3

Diagram of standard deviation

Answer 3

https://www.thoughtco.com/thmb/qmSnmY_b1ztjvvdp-QhdT4-DA8c=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/calculate-a-sample-standard-deviation-3126345-v4-CS-01-5b76f58f46e0fb0050bb4ab2.png

Question 4

T test

Answer 4

1) x = mean of sample 1 and 2 and take away sample 1 mean from 2
2)square the standard deviation from first sample
3)divide S by N of sample 1
4)repeat step 2 + 3 with sample 2
5)add value of answer of sample 1+2
6)square root it
7)divide value of step 1 with value from step 6

Answer = t value
Degree of freedom = (n from sample 1 - 1) + (n from sample 2 - 1)
Compare to critical value of 0.05 probability to see if null hypothesis accepted or rejected

Question 5

Diagram of t test

Answer 5

https://microbenotes.com/wp-content/uploads/2023/08/Two-Sample-T-Test-Formula.jpeg