Relative Risk Ratios And Odds Ratios
You can switch back and forth between probability and odds—both give you the same information, just on different scales If O1 is the odds of event in the Treatment group and O2 is the odds of event in the control group then the odds ratio is O1/O2 Just like the risk ratio, it's a way of measuring the effect of the tutoring program on the odds of an event Compare this to RR which The Ask Dr Math forum has several entries on odds versus probability Summarizing, one way to conceptualize (nontechnically) the probability of an event is the number of ways that an event can occur divided by the total number of possible outcomes The probability of heads in a fair coin flip is 1/2 (50 percent) The probability of drawing a red card from a standard deck of
