If a test that has reliability r is lengthened by a factor , the reliability R of the new test is given by
If the reliability is r = 0.5, the equation becomes . When the test length is unchanged, the reliability r = R(1) = 0.5. If the length of the test is doubled, the reliability r = R(2). What percent improvement is there in the reliability when the test length is doubled?

A) 25.0%
B) 33.3%
C) 75.0%
D) 66.7%
E) 16.7%

Question

If a test that has reliability r is lengthened by a factor  , the reliability R of the new test is given by ​  ​
​If the reliability is r = 0.5, the equation becomes  . When the test length is unchanged, the reliability r = R(1) = 0.5. If the length of the test is doubled, the reliability r = R(2). What percent improvement is there in the reliability when the test length is doubled?
​
A) 25.0% 
B) 33.3% 
C) 75.0% 
D) 66.7% 
E) 16.7%

Quizplus · Accepted Answer

The Answer of If a test that has reliability r is lengthened by a factor  , the reliability R of the new test is given by ​  ​
​If the reliability is r = 0.5, the equation becomes  . When the test length is unchanged, the reliability r = R(1) = 0.5. If the length of the test is doubled, the reliability r = R(2). What percent improvement is there in the reliability when the test length is doubled?
​
A) 25.0% 
B) 33.3% 
C) 75.0% 
D) 66.7% 
E) 16.7%

If a Test That Has Reliability R Is Lengthened by a Factor