Reliability Homework

 

This is assignment is for Measurement and Evaluation for Health Educators

Reliability Homework

Instructions: You may use your book to find the appropriate formula. To receive full credit, you must write out the formula and show all of your work. Please make sure you put your name on the paper.  Each question is worth 10 points for a total of 50 points.

1. Calculate Cronbach’s alpha where N=500      and p=0.25. Provide your      recommendation based on the alpha level obtained.
2. Calculate Cronbach’s alpha where N=75 and      p=0.05. Provide your recommendation      based on the alpha level obtained.
3. Calculate Cohen’s kappa for Interobserver      reliability where  Pr(a)=35 and Pr (e)=25. Provide your recommendation based on the kappa  level obtained. 
4. Calculate Cohen’s kappa for Interobserver      reliability where  Pr(a)=68 and Pr (e)= 60. Provide your recommendation based on the kappa  level obtained.
5. Calculate the percent agreement where the      # of agreements  =350 and the # of disagreements =82. Provide your recommendation based  on the      percent agreement obtained.

§ Formula

α= Np / [1+ p(N-1)]

§ Components of the formula

α = Cronbach’s alpha

N= number of items

P= mean inter-item correlations

§ Interpretation

v Range from 0 to 1

v Higher the value, the stronger the internal consistency

v Acceptable minimum 0.70