Use a 001 level of significance to test whether the differen
Use a 0.01 level of significance to test whether the difference between the means of these two samples is significant. Assume equal variance between populations.
The t-statistic for this test is t0 =
b)Based on the t-statistic calculated above, the null hypothesis must be rejected at a level of significance equal to 0.01. We conclude that the average heat-producing capacity of the coal from the two mines is not the same. The very small P value 0.0024 strengthens this conclusion. Enter 0 if this statement is FALSE or 1 otherwise
The following are the average weekly losses of worker-hours due to accidents in 10 industrial plants before and after a certain safety program was put into operation BEFORE Plant 1: 45 Plant 2: 73 Plant 3: 46 Plant 4:124 Plant 5: 33 Plant 6: 57 Plant 7: 83 Plant 8: 34 Plant 9: 26 Plant 10: 17 AFTER Plant 1: 36 Plant 2: 60 Plant 3: 44 Plant 4:119 Plant 5: 35 Plant 6: 51 Plant 7: 77 Plant 8: 29 Plant 9: 24 Plant 10: 11 Conduct a paired t test to analyze this problem. Use the 0.05 level of significance to test whether the safety program is effectiveSolution
Let ud = u2 - u1.              
 Formulating the null and alternative hypotheses,              
               
 Ho:   ud   =   0  
 Ha:   ud   =/   0  
 At level of significance =    0.01          
 As we can see, this is a    two   tailed test.      
               
 Calculating the standard deviation of the differences (third column):              
               
 s =    311.5875284          
               
 Thus, the standard error of the difference is sD = s/sqrt(n):              
               
 sD =    98.53262804          
               
 Calculating the mean of the differences (third column):              
               
 XD =    102.8          
               
 As t = [XD - uD]/sD, where uD = the hypothesized difference =    0   , then      
               
 t =    1.043309227 [ANSWER, T STATISTIC]
*********************************          
               
 Additional info:
As df = n - 1 =    9          
               
 Then the critical value of t is              
               
 tcrit =    +/-   3.249835542      
               
 Thus, comparing t and tcrit, we   WE FAIL TO REJECT THE NULL HYPOTHESIS.          
               
 Also, using p values,              
               
 p =        0.324017857      
               
 Also, comparing this p to the significance level,   WE FAIL TO REJECT THE NULL HYPOTHESIS.          
   
*************************
The part B seems to be a different problem, and has insufficient given.
Please submit this part as a separate question. That way we can continue helping you! Please indicate which parts are not yet solved when you submit. Thanks!


