"Achievement Test Scores Are Declining All Around Us,"brooded Professor Probity

Essay

"Achievement test scores are declining all around us,"brooded Professor Probity. "Not in my class,"vouchsafed Professor Paragon. "Here are my final-exam scores for last year and this year on the same exam. Run your own t test on them. Calculate the effect size index."What did Probity discover? $$\begin{array} { c c } \text { Last Year } & \text { This Year } \\\hline 29 & 27 \\27 & 28 \\26 & 25 \\22 & 24 \\19 & 22 \\15 & 20 \\14 & 18 \\13 & 16 \\10 & 12\end{array}$$