T-test

• Tell you if there is a statistically significant difference between two means, when sample is under 25 data is normally distributed
• Students T-test (unpaired) formula

  X_1 = mean of first sample

  X_2 = mean of second sample

  S_1 = standard deviation of first sample

  S_2 = standard deviation of second sample

  n_1 = number of measurements in first sample

  n_2 = number of measurements in second sample

  
• Null hypothesis (H_0): there is no statistically significant difference between the two means of the data, it can be rejected if the value for t exceeds the critical value (P = 0.05)