z/t/F/X^2 https://ocw.mit.edu/courses/mathematics/18-05-introduction-to-probability-and-statistics-spring-2014/related-resources/MIT18_05S14_nhst.pdf more about paired t test great plot for the relationships of significant tests http://www2.sci.u-szeged.hu/eghajlattan/pdf/11-12%20Statistical%20tests%20anova.pdf