Statistical Sciences 2037A/B Chapter Notes - Chapter 5: Dependent And Independent Variables, Confounding, Randomized Experiment

• School: Western University
• Department: Statistical Sciences
• Course: Statistical Sciences 2037A/B
• Professor: Emad Mohammad

Document Summary

Explanatory variable attempts to explain/cause differences in response variable. Treatment combination of categories of the explanatory variable assigned by the experimenter, incorporates a collection of conditions. Randomized experiment create differences in the explanatory variable. Observational study observe differences in explanatory variable and see if it is related to response variable. We may use observational study over an experiment because the experiment may be unethical or explanatory variable can"t be randomly assigned (what hand do you write with) Confounding variable one that has 2 properties. It is related to the explanatory variable (differ in explanatory variable means they will differ in the confounding variable). It also affects the explanatory variable (this effect cannot be separated). (example: smoking affects iq, nutrition affects iq, smoking and nutrition are related) The effect of one explanatory variable on a response variable depends on the state of another explanatory variable. Experimental units smallest basic object to which we can assign different treatments in a randomized experiment.