Suppose That I Performed a Reliability Analysis to Determine Whether

question 3

Essay

Suppose that I performed a reliability analysis to determine whether high school students' grades in four different subjects (English, Math, Science, Social Studies) formed a reliable scale with a high Cronbach's alpha. I performed the analysis and got the results presented in the two tables below.
$\begin{array}{c}\text { Reliab ility Statistics }\\\begin{array}{|r|r|}\hline \begin{array}{c}\text { Cronbach's } \\\text { Alpha }\end{array} & \text { N of Items } \\\hline .892 & 4 \\\hline\end{array}\end{array}$ $\begin{array}{|l|c|r|r|r|}\hline & \begin{array}{c}\text { Scale Mean } \\\text { if Item } \\\text { Deleted }\end{array} & \begin{array}{c}\text { Scale } \\\text { Variance if } \\\text { Item Deleted }\end{array} & \begin{array}{c}\text { Corrected } \\\text { Item-Total } \\\text { Correlation }\end{array} & \begin{array}{c}\text { Cronbach's } \\\text { Alpha if Item } \\\text { Deleted }\end{array} \\\hline \text { English grade } & 21.9358 & 111.296 & .769 & .859 \\\text { Math grade } & 23.1301 & 109.392 & .700 & .886 \\\text { Science grade } & 22.1658 & 105.074 & .801 & .847 \\\text { Social studies grade } & 21.5330 & 110.514 & .787 & .853 \\\hline\end{array}$ a. What is the reliability of this scale, as indicated by the Cronbach's alpha. Is this a high or low level of reliability?
b. Which item seems to be contributing the least to the overall Cronbach's alpha?
c. Which item, if any, would you recommend removing from this scale?

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