simulation on ouR data generation
https://www.rdatagen.net/tags/simulation/
Recent content in simulation on ouR data generationHugo -- gohugo.iokeith.goldfeld@nyumc.org (Keith Goldfeld)keith.goldfeld@nyumc.org (Keith Goldfeld)Tue, 03 Sep 2024 00:00:00 +0000An IV study design to estimate an effect size when randomization is not ethical
https://www.rdatagen.net/post/2024-09-03-an-instrumental-variable-study-design-to-estimate-an-effect-size-when-randomization-may-not-be-ethical/
Tue, 03 Sep 2024 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2024-09-03-an-instrumental-variable-study-design-to-estimate-an-effect-size-when-randomization-may-not-be-ethical/An investigator I frequently consult with seeks to estimate the effect of a palliative care treatment protocol for patients nearing end-stage disease, compared to a more standard, though potentially overly burdensome, therapeutic approach. Ideally, we would conduct a two-arm randomized clinical trial (RCT) to create comparable groups and obtain an unbiased estimate of the intervention effect. However, in this case, it may be considered unethical to randomize patients to a non-standard protocol.Generating binary data by specifying the relative risk, with simulations
https://www.rdatagen.net/post/2024-07-02-generating-binary-data-by-specifying-relative-risk/
Tue, 02 Jul 2024 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2024-07-02-generating-binary-data-by-specifying-relative-risk/The most traditional approach for analyzing binary outcome data is logistic regression, where the estimated parameters are interpreted as log odds ratios or, if exponentiated, as odds ratios (ORs). No one other than statisticians (and maybe not even statisticians) finds the odds ratio to be a very intuitive statistic, and many feel that a risk difference or risk ratio/relative risks (RRs) are much more interpretable. Indeed, there seems to be a strong belief that readers will, more often than not, interpret odds ratios as risk ratios.Flexible simulation in simstudy with customized distribution functions
https://www.rdatagen.net/post/2022-08-30-expanding-the-possibilities-of-simulation-in-simstudy-with-customized-distribution-funcdtions/
Tue, 30 Aug 2022 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2022-08-30-expanding-the-possibilities-of-simulation-in-simstudy-with-customized-distribution-funcdtions/Really, the only problem with the simstudy package (😄) is that there is a hard limit to the possible probability distributions that are available (the current count is 15 - see here for a complete description). However, it turns out that there is more flexibility than first meets the eye, and we can easily accommodate a limitless number as long as you are willing to provide some extra code.Simulating data from a non-linear function by specifying a handful of points
https://www.rdatagen.net/post/2022-08-09-simulating-data-from-a-non-linear-function-by-specifying-some-points-on-the-curve/
Tue, 09 Aug 2022 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2022-08-09-simulating-data-from-a-non-linear-function-by-specifying-some-points-on-the-curve/Trying to simulate data with non-linear relationships can be frustrating, since there is not always an obvious mathematical expression that will give you the shape you are looking for. I’ve come up with a relatively simple solution for somewhat complex scenarios that only requires the specification of a few points that lie on or near the desired curve. (Clearly, if the relationships are straightforward, such as relationships that can easily be represented by quadratic or cubic polynomials, there is no need to go through all this trouble.simstudy updated to version 0.5.0
https://www.rdatagen.net/post/2022-07-20-simstudy-updated-to-version-0-5-0/
Wed, 20 Jul 2022 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2022-07-20-simstudy-updated-to-version-0-5-0/A new version of simstudy is available on CRAN. There are two major enhancements and several new features. In the “major” category, I would include (1) changes to survival data generation that accommodate hazard ratios that can change over time, as well as competing risks, and (2) the addition of functions to allow users to sample from existing data sets with replacement to generate “synthetic” data will real life distribution properties.Simulating survival outcomes: setting the parameters for the desired distribution
https://www.rdatagen.net/post/2022-02-08-simulating-survival-outcomes-setting-the-parameters-for-the-desired-distribution/
Tue, 08 Feb 2022 00:00:00 +0000keith.goldfeld@nyumc.org (Keith Goldfeld)https://www.rdatagen.net/post/2022-02-08-simulating-survival-outcomes-setting-the-parameters-for-the-desired-distribution/The package simstudy has some functions that facilitate generating survival data using an underlying Weibull distribution. Originally, I added this to the package because I thought it would be interesting to try to do, and I figured it would be useful for me someday (and hopefully some others, as well). Well, now I am working on a project that involves evaluating at least two survival-type processes that are occurring simultaneously.