Question

In a study, researchers considered the question of whether one side of the brain might be better attuned to identifying similar objects, while the other side of the brain might do better at distinguishing when objects are different. . The mean reaction times (msec) for the subjects to reach their conclusions about six sets of differently oriented parallel lines (i.e., same lines) in the left visual field (LVF) and the same six sets of parallel lines in the right visual field (RVF) are given in Table below.

Subject	LVF	RVF
1	471	493
2	477	524
3	303	345
4	428	444
5	418	423
6	517	499
7	412	385
8	381	444
9	343	363
10	390	390
11	501	514
12	429	467
13	439	473
14	377	390
15	402	429

(b). Find a 99% confidence interval for the difference between LVF and RVF mean reaction times for right-handed people to identify parallel pairs of lines.(a). Is it reasonable to conclude that right-handed subjects differentially use the right and left sides of their brain to identify similar objects.? Use α = 0.01?

Answer 1

b)

mean of sample 1,    x̅1=   419.200                  
                          
mean of sample 2,    x̅2=   438.867                  
                          
mean of difference ,    D̅ =ΣDi / n =   -19.667                  
                          

sample size ,    n =    15          
Degree of freedom, DF=   n - 1 =    14   and α =    0.01  
t-critical value =    t α/2,df =    2.9768   [excel function: =t.inv.2t(α/2,df) ]      
                  
std dev of difference , Sd =    √ [ (Di-Dbar)²/(n-1) =    23.9424          
                  
std error , SE = Sd / √n =    23.9424   / √   15   =   6.1819
margin of error, E = t*SE =    2.9768   *   6.1819   =   18.4025
                  
mean of difference ,    D̅ =   -19.667          
confidence interval is                   
Interval Lower Limit= D̅ - E =   -19.667   -   18.4025   =   -38.069
Interval Upper Limit= D̅ + E =   -19.667   +   18.4025   =   -1.264
                  
so, confidence interval is (   -38.0692   < µd <   -1.2641   )  

Since Confidence interval does not contain zero, we can reject the null hypothesis.

It is reasonable to conclude that right-handed subjects differentially use the right and left sides of their brain to identify similar objects

Thanks in advance!

revert back for doubt

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