Turn on suggestions

Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.

Showing results for

- JMP User Community
- :
- Discussions
- :
- Re: Need help with Bootstrap

Topic Options

- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Oct 13, 2017 6:50 AM
(5085 views)

I am doing a proportional hazards model and trying to do a bootstrap for the risk ratios. I can't provide my data, but since I keep getting the same error in both my data and a simple JMP example for the sample data library, I am attaching that example here. I run the proportional hazards model, focusing on the risk ratios for two groups (which I set up at random) - a test group and a control group. I click on the risk ratio estimates and attempt a bootstrap analysis - but I keep getting the error that it failed to converge. I understand generally what the bootstrap sample is doing and that nonconvergence is a possibility, but since I get this error every time - and with any data I try it with - I suspect I am doing something wrong. Please let me know if you can see a reason why my bootstrap keeps failing. Thank you.

1 ACCEPTED SOLUTION

Accepted Solutions

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Hello, I'm not sure why it's failing to converge. Have you tried using the Fractional Weights option when you do the Bootstrap? That can help in situations where there aren't a lot of observations in particular cells. In this case, that would be cells in the Censor * group 2-by-2 contingency table.

Michael

Michael

Michael Crotty

Sr Statistical Writer

JMP Development

Sr Statistical Writer

JMP Development

5 REPLIES 5

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Re: Need help with Bootstrap

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Michael

Michael Crotty

Sr Statistical Writer

JMP Development

Sr Statistical Writer

JMP Development

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Re: Need help with Bootstrap

Highlighted
##

Fractional weights works very well for me - I had the same problem. When the event is rare enough, the bootstrap often does not converge. The Fractional weights use all of the observations, so in my experience, it always converges. It is a terrific feature!

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Re: Need help with Bootstrap

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Get Direct Link
- Email to a Friend
- Report Inappropriate Content

Re: Need help with Bootstrap

Glad to hear that it's working for you!

Michael Crotty

Sr Statistical Writer

JMP Development

Sr Statistical Writer

JMP Development