Intro to Statistics

Scientists collect a sample of the population that is (ideally) representative of a general population.

Graph the data and analyze the distribution of it

• Data will typically show normal distribution (the bell curve)

Central Tendency - Quantify and examine differences (mode, mean, median)

• Mean is good for regular distributions

• Median is good for abnormal distributions / large amount of outliers

Variability - How far a dataset diverges from a central tendency (range and standard distribution)

• Standard distribution - A measure of how far spread out the data is from the mean

  • 68-95-99.7 rule

Standard error - used to determine the precision and confidence of the mean (and how well it represents the population)

• Based on standard deviation and the amount of data points

  • +/- 2 SE = 95% confidence