Hello, everyone
I managed to estimate the parameters for a Weibull accelerated failure time model from the PROC LIFEREG procedure. I have the point and interval estimations for predictor coefficients. In addition, I have the estimations for the Weibull shape parameter.
After I get these estimations, I would like to simulate the cumulative incidence curve/survival curve. I know I should use the point estimation of these coefficients and the shape parameter in the prediction model. But I am not sure whether to use the interval estimation of coefficients, or the shape parameter.
You answer is much appreciated!
... View more
Please help me with error: Error: The connection could not be established to a SAS Workspace Server named 'Local' running on port on host 'localhost'. Please verify the following: - The correct hostname and port number were specified. - If a firewall is present, it is correctly configured to allow this access. - An object spawner has been started on the server. - The SETINIT on the server is not expired. Please contact your SAS Administrator if the problem persists. Server response: Server execution failed
... View more
I am currently analyzing the impact of an intervention on medication numbers using difference-in-difference analysis, but I have encountered several challenges. Following the SAS support instructions, I conducted the difference-in-difference analysis. However, I noticed a discrepancy between my results and SAS's example (Usage Note 61830: Estimating the difference in differences of means). In the example, the value of 'Mean Estimate' in 'Contrast Estimate Results' is identical to the 'Estimate' in 'Least Squares Means Estimate'. However, in my case, these values were different. I suspect this could be due to my use of the negative binomial distribution with a log link, resulting in exponential values. Consequently, I am unsure whether to rely on the 'Mean Estimate' in 'Contrast Estimate Results' or the 'Estimate' in 'Least Squares Means Estimate', and how to interpret the results." Contrast Estimate Results Label Mean Estimate Mean Confidence Limits L'Beta Estimate Standard Error diff in diff 1.51 1.49 0.41 0.0051 a*b Least Squares Means a b Estimate Standard Error z value Pr > |z| 1 1 0.77 0.00434 178.19 <.0001 1 0 0.03 0.00508 6.5 <.0001 0 1 0.72 0.00408 177.71 <.0001 0 0 0.40 0.00426 93.11 <.0001 Least Squares Means Estimate Effect Label Estimation Standard Error z value Pr > |z| time*hospitalize diff in diff 0.41 0.00509 81.01 <.0001
... View more