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- Strong convergence of rotation by 1/n operators
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- One property of characteristic function (probability)
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- Change to polar coordinate in ODEs
- Equivalent norms on a field differ only by a power
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- Expressing conditional entropy as a relative entropy
- Use the Inverse Power Method Iteration Method to Determine the Eigenvectors (already knowing the eigenvalues)
- Find the rectangular regions where the initial value problem has unique solution
- Understanding formula for hyperplanes
- Kronecker delta: in $3-$ dimension $\delta_{ii}=3$
- What are the facets of the Birkhoff Polytope when $n=2$.
- Solving $\sqrt{\frac{\log\left(x + a + n\right)}{a}} - \sqrt{\frac{\log\left(x + a + n\right)}{x}} = \Phi$ for $x$
- Sparse group lasso derivation of soft thresholding operator via subgradient equations
- How the definition of the truth table of the material implication (&p⇒q&), is “derived” from the definition of a valid argument?

# Suggested method for data with assumed non-proportional hazards

We are planning a study on longitudinal healtcare data. Exposure is starting a certain medication ("A"). Controls are those in the dataset not starting A, matched on age, sex and some other variables. Outcome is the presence of a laboratory value below a certain threshold on the first test after initiating A (ie binary outcome of interest). The time to the first testing of this laboratory value can vary considerably. In consequence, we assume that hazards will be non-proportional (time to event depends on when testing takes place rather than being related to risk).

What other methods than Cox proportional hazards model could be recommended in this context?

Requirements on the model include:

Can be used with non-proportional hazards (which we assume a priori).

Censoring (eg death of the patient or end of follow up).

Multivariable adjustment using both categorical and continuous predictors.

Can model competing risks (other outcomes related to A that invalidate the out