Question

1. There are 25 students who started computer programming in elementary school and 25 students who started computer programming in middle school. The first group had a mean final project grade of 95% and the second group had a mean final project grade of 92%.
The line plot shows the differences after 10 rerandomizations. Determine whether the difference in the means of the two groups is significant based on the line plot. Explain your answer.

Answer 1

Answer:

The difference in the means of the two groups is significant based on the line plot.

Step-by-step explanation:

Given that n1 = 25 and n2 =25 which are the students who started computer programming in elementary and middle school respectively.

Let x bar represent average for elementary and y bar for middle school.

H0: x bar = y bar

Ha: x bar not equals y bar

(Two tailed test)

The line plot gives the differences of sample size 10

Let d = difference = |x bar-y bar|

Then

    Total

     

d 1 2 3 4  

Freq 1 2 4 3 10

d*f 1 4 12 12 29

d^2 *f 1 8 36 48 93

     

Mean d 2.9    

Var d 0.89    

Std dev d 0.943398113    

Std error d 0.314466038    

     

Test statistic 9.221981556    

df 9    

p <0.0001    

Since p < 0.05, at 95% level we conclude that there is a significant difference between the two means.

The line plot shows the differences