Related Experiment Video
Updated: Jun 11, 2026

Creating Objects and Object Categories for Studying Perception and Perceptual Learning
Published on: November 2, 2012
Comparing simulation and threshold approaches when analysing data with probabilities of categories
Fang Zhang1, J Frank Wharam, Dennis Ross-Degnan
1Department of Ambulatory Care and Prevention, Harvard Medical School and Harvard Pilgrim Health Care, Boston, MA 02215, USA. fang_zhang@hphc.org
Objective:
Constructing categories based on probabilities is not unusual in defining the outcome or the exposure. We compare the threshold approach and the simulation approach in making inferences.
Method:
We used a simple structured example as well as published data to illustrate the difference between the simulation and the threshold approaches.
Results:
We demonstrated that simulation results were different from the threshold approach in estimating the effect of a high-deductible health plan. For repeat visits, we estimated a statistically significant ratio of incident rate ratio (IRR) 0.78 (95% CI: 0.64, 0.93) for non-preventable emergency department visits using the simulation approach while the high-severity category showed no statistical significance with the ratio of IRR 0.98 (95% CI: 0.64, 1.49) using a threshold of 75%. We also demonstrated that none of the threshold values could achieve the results of the simulation approach.
Conclusions:
The simulation approach is preferred over the threshold one when analysing data with probability-based outcome, exposure and/or other covariates if the size of the data permits.
Related Concept Videos
Testing a Claim about Population Proportion
There are two methods of testing a claim about a population proportion: (1) Using the sample proportion from the data where a binomial distribution is approximated to the normal distribution and (2) Using the binomial probabilities calculated from the data.
The first method uses normal distribution as an approximation to the binomial distribution. The requirements are as follows: sample size is large...
Comparing the Survival Analysis of Two or More Groups
Expected Frequencies in Goodness-of-Fit Tests
Decision Making: Traditional Method
First, a specific claim about the population parameter is decided based on the research question and is stated in a simple form. Further, an opposing statement to this claim is also stated. These statements can act as null and alternative hypotheses, out of which a null hypothesis would be a...
Probability in Statistics
An example of a simple event is a coin toss. The result of a coin toss is either a head or a tail. Here, head and tail are two simple events. These two simple events make up the sample space. Further, the probability of an event occurring falls within the range of 0 to 1. The probability of an...
Probability Histograms

