Support for `emp_start` to apply to other non-spatial covariance structures

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#562 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Quiet
Tech stack
r
Domain
data

Research direction

Start at the existing emp_start entry point and trace how it derives starting values for us covariance estimation. Then inspect the other non-spatial covariance structures and determine the reasonable empirical-covariance starting values needed for each. Done means emp_start provides useful starts for those structures before the general optimization loop.

Written by the indexing model from the issue text.

Description

enhancement

Summary

The current function emp_start works well to speed up us covariance estimation. I would like to extend this to the other non-spatial covariance structures so that we start with a close approximation before going into a general optimization loop.

Additional Information

Essentially, the existing emp_start need only use an additional helper function that calculates a reasonable starting value for non-us covariance structures from the empirical covariance matrix.

Dominant language
R
Stars
162
Forks
29
Avg merge
1d 9h
Merged PRs (30d)
2

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