1. t-tests Quantitative Data One group  1-sample t-test Two independent groups  2-sample t-test Two dependent groups  Matched Pairs t-test t-TestsSlide #1

2. t-TestsSlide #2 A Full Reality No longer know what  is!!!!! What should be used instead? –Our best guess at   s Changes details, not the big picture t

3. t-TestsSlide #3 Student’s t-distribution Compared to a standard normal (Z): Similarities –symmetric about 0 –approximately bell-shaped Differences –more probability in the tails –less probability in the center –Exact shape depends on degrees-of-freedom (df) See “t distribution in R” video -4-2024 Z or t 1 df 2 df 5 df10 df