changeset 19106:afc1a8965664

Move lscov.m from optimization directory to statistics/base/ (bug #43118) * scripts/optimization/lscov.m: remove lscov.m * scripts/statistics/base/lscov.m: add lscov.m side by side with ols.m and gls.m which have a similar interface/purpose
author Pantxo Diribarne <pantxo.diribarne@gmail.com>
date Mon, 08 Sep 2014 08:09:45 +0200
parents c9113e28fae8
children ec1e295402fa
files scripts/optimization/lscov.m scripts/optimization/module.mk scripts/statistics/base/lscov.m scripts/statistics/base/module.mk
diffstat 4 files changed, 188 insertions(+), 188 deletions(-) [+]
line wrap: on
line diff
--- a/scripts/optimization/lscov.m	Sun Sep 07 11:30:41 2014 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,187 +0,0 @@
-## Copyright (C) 2014 Nir Krakauer
-##
-## This program is free software; you can redistribute it and/or modify
-## it under the terms of the GNU General Public License as published by
-## the Free Software Foundation; either version 3 of the License, or
-## (at your option) any later version.
-##
-## This program is distributed in the hope that it will be useful,
-## but WITHOUT ANY WARRANTY; without even the implied warranty of
-## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-## GNU General Public License for more details.
-##
-## You should have received a copy of the GNU General Public License
-## along with this program; If not, see <http://www.gnu.org/licenses/>.
-
-## -*- texinfo -*-
-## @deftypefn  {Function File} {@var{x} =} lscov (@var{A}, @var{b})
-## @deftypefnx {Function File} {@var{x} =} lscov (@var{A}, @var{b}, @var{V})
-## @deftypefnx {Function File} {@var{x} =} lscov (@var{A}, @var{b}, @var{V}, @var{alg})
-## @deftypefnx {Function File} {[@var{x}, @var{stdx}, @var{mse}, @var{S}] =} lscov (@dots{})
-##
-## Compute a generalized linear least squares fit.
-## Estimate @var{x} under the model @var{b} = @var{A}@var{x} + @var{w}, 
-## where the noise @var{w} is assumed to follow a normal distribution 
-## with covariance matrix @math{{\sigma^2} V}.
-##
-## If the size of the coefficient matrix @var{A} is n-by-p, the
-## size of the vector/array of constant terms @var{b} must be n-by-k.
-##
-## The optional input argument @var{V} may be a n-by-1 vector of positive
-## weights (inverse variances), or a n-by-n symmetric positive
-## semidefinite matrix representing the covariance of @var{b}. If
-## @var{V} is not supplied, the ordinary least squares solution is
-## returned.
-##
-## The @var{alg} input argument, a guidance on solution method to use,
-## is currently ignored.
-##
-## Besides the least-squares estimate matrix @var{x} (p-by-k), the
-## function also returns @var{stdx} (p-by-k), the error  standard
-## deviation of estimated @var{x}; @var{mse} (k-by-1), the estimated
-## data error covariance scale factors (@math{\sigma^2}); and @var{S}
-## (p-by-p, or p-by-p-by-k if k > 1), the error covariance of @var{x}.
-##
-## Reference: Golub and Van Loan (1996), Matrix Computations (3rd Ed.), Johns Hopkins, Section 5.6.3
-##
-## @end deftypefn
-## @seealso{ols, gls, lsqnonneg}
-
-## Author: Nir Krakauer
-
-function [x, stdx, mse, S] = lscov (A, b, V = [], alg)
-
-  if (nargin < 2 || (rows (A) != rows (b)))
-    print_usage ();
-  endif
-  
-  n = rows (A);
-  p = columns (A);
-  k = columns (b);
-  
-  if (! isempty (V))
-    if (rows (V) != n || ! any (columns (V) == [1 n]))
-      error ("lscov: V should be a square matrix or a vector with the same number of rows as A");
-    endif
-    
-    if (isvector (V))
-      ## n-by-1 vector of inverse variances
-      v = diag (sqrt (V));
-      A = v * A;
-      b = v * b;
-    else
-      ## n-by-n covariance matrix
-      try
-        ## ordinarily V will be positive definite
-        B = chol (V)';
-      catch
-        ## if V is only positive semidefinite, use its
-        ## eigendecomposition to find a factor B such that V = B*B'
-        [B, lambda] = eig (V);
-        image_dims = (diag (lambda) > 0);
-        B = B(:, image_dims) * sqrt (lambda(image_dims, image_dims));
-      end_try_catch     
-      A = B \ A;
-      b = B \ b;
-    endif
-  endif
-  
-  pinv_A = pinv (A); #pseudoinverse
-
-  x = pinv_A * b;
-  
-  if (isargout (3))
-    dof = n - p; #degrees of freedom remaining after fit
-    SSE = sumsq (b - A * x);
-    mse = SSE / dof;
-  endif
-  
-  s = pinv_A * pinv_A';
-
-  stdx = sqrt (diag (s) * mse);
-  
-  if (isargout (4))
-    if (k == 1)
-      S = mse * s;
-    else
-      S = nan (p, p, k);
-      for i = 1:k
-        S(:, :, i) = mse(i) * s;
-      endfor
-    endif
-  endif
-endfunction
-
-%!test
-%! ## Longley data from the NIST Statistical Reference Dataset
-%! Z = [  60323    83.0   234289   2356     1590    107608  1947
-%!        61122    88.5   259426   2325     1456    108632  1948
-%!        60171    88.2   258054   3682     1616    109773  1949
-%!        61187    89.5   284599   3351     1650    110929  1950
-%!        63221    96.2   328975   2099     3099    112075  1951
-%!        63639    98.1   346999   1932     3594    113270  1952
-%!        64989    99.0   365385   1870     3547    115094  1953
-%!        63761   100.0   363112   3578     3350    116219  1954
-%!        66019   101.2   397469   2904     3048    117388  1955
-%!        67857   104.6   419180   2822     2857    118734  1956
-%!        68169   108.4   442769   2936     2798    120445  1957
-%!        66513   110.8   444546   4681     2637    121950  1958
-%!        68655   112.6   482704   3813     2552    123366  1959
-%!        69564   114.2   502601   3931     2514    125368  1960
-%!        69331   115.7   518173   4806     2572    127852  1961
-%!        70551   116.9   554894   4007     2827    130081  1962 ];
-%! ## Results certified by NIST using 500 digit arithmetic
-%! ## b and standard error in b
-%! V = [  -3482258.63459582         890420.383607373
-%!         15.0618722713733         84.9149257747669
-%!        -0.358191792925910E-01    0.334910077722432E-01
-%!        -2.02022980381683         0.488399681651699
-%!        -1.03322686717359         0.214274163161675
-%!        -0.511041056535807E-01    0.226073200069370
-%!         1829.15146461355         455.478499142212 ];
-%! rsd =  304.854073561965;
-%! y = Z(:,1); X = [ones(rows(Z),1), Z(:,2:end)];
-%! alpha = 0.05;
-%! [b, stdb, mse] = lscov (X, y);
-%! assert(b, V(:,1), 3e-6);
-%! assert(stdb, V(:,2), -1.e-5);
-%! assert(sqrt (mse), rsd, -1E-6);
-
-%!test
-%! ## Adapted from example in Matlab documentation
-%! x1 = [.2 .5 .6 .8 1.0 1.1]'; 
-%! x2 = [.1 .3 .4 .9 1.1 1.4]'; 
-%! X = [ones(size(x1)) x1 x2]; 
-%! y = [.17 .26 .28 .23 .27 .34]';
-%! [b, se_b, mse, S] = lscov(X, y);
-%! assert(b, [0.1203 0.3284 -0.1312]', 1E-4);
-%! assert(se_b, [0.0643 0.2267 0.1488]', 1E-4);
-%! assert(mse, 0.0015, 1E-4);
-%! assert(S, [0.0041 -0.0130 0.0075; -0.0130 0.0514 -0.0328; 0.0075 -0.0328 0.0221], 1E-4);
-%! w = [1 1 1 1 1 .1]'; 
-%! [bw, sew_b, msew] = lscov (X, y, w);
-%! assert(bw, [0.1046 0.4614 -0.2621]', 1E-4);
-%! assert(sew_b, [0.0309 0.1152 0.0814]', 1E-4);
-%! assert(msew, 3.4741e-004, -1E-4);
-%! V = .2*ones(length(x1)) + .8*diag(ones(size(x1)));
-%! [bg, sew_b, mseg] = lscov (X, y, V);
-%! assert(bg, [0.1203 0.3284 -0.1312]', 1E-4);
-%! assert(sew_b, [0.0672 0.2267 0.1488]', 1E-4);
-%! assert(mseg, 0.0019, 1E-4);
-%! y2 = [y 2*y];
-%! [b2, se_b2, mse2, S2] = lscov (X, y2);
-%! assert(b2, [b 2*b])
-%! assert(se_b2, [se_b 2*se_b])
-%! assert(mse2, [mse 4*mse])
-%! assert(S2(:, :, 1), S)
-%! assert(S2(:, :, 2), 4*S)
-
-%!test
-%! ## Artificial example with positive semidefinite weight matrix
-%! x = (0:0.2:2)';
-%! y = round(100*sin(x) + 200*cos(x));
-%! X = [ones(size(x)) sin(x) cos(x)];
-%! V = eye(numel(x));
-%! V(end, end-1) = V(end-1, end) = 1;
-%! [b, seb, mseb, S] = lscov (X, y, V);
-%! assert(b, [0 100 200]', 0.2);
--- a/scripts/optimization/module.mk	Sun Sep 07 11:30:41 2014 +0200
+++ b/scripts/optimization/module.mk	Mon Sep 08 08:09:45 2014 +0200
@@ -11,7 +11,6 @@
   optimization/fsolve.m \
   optimization/fzero.m \
   optimization/glpk.m \
-  optimization/lscov.m \
   optimization/lsqnonneg.m \
   optimization/optimget.m \
   optimization/optimset.m \
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/statistics/base/lscov.m	Mon Sep 08 08:09:45 2014 +0200
@@ -0,0 +1,187 @@
+## Copyright (C) 2014 Nir Krakauer
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; If not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {@var{x} =} lscov (@var{A}, @var{b})
+## @deftypefnx {Function File} {@var{x} =} lscov (@var{A}, @var{b}, @var{V})
+## @deftypefnx {Function File} {@var{x} =} lscov (@var{A}, @var{b}, @var{V}, @var{alg})
+## @deftypefnx {Function File} {[@var{x}, @var{stdx}, @var{mse}, @var{S}] =} lscov (@dots{})
+##
+## Compute a generalized linear least squares fit.
+## Estimate @var{x} under the model @var{b} = @var{A}@var{x} + @var{w}, 
+## where the noise @var{w} is assumed to follow a normal distribution 
+## with covariance matrix @math{{\sigma^2} V}.
+##
+## If the size of the coefficient matrix @var{A} is n-by-p, the
+## size of the vector/array of constant terms @var{b} must be n-by-k.
+##
+## The optional input argument @var{V} may be a n-by-1 vector of positive
+## weights (inverse variances), or a n-by-n symmetric positive
+## semidefinite matrix representing the covariance of @var{b}. If
+## @var{V} is not supplied, the ordinary least squares solution is
+## returned.
+##
+## The @var{alg} input argument, a guidance on solution method to use,
+## is currently ignored.
+##
+## Besides the least-squares estimate matrix @var{x} (p-by-k), the
+## function also returns @var{stdx} (p-by-k), the error  standard
+## deviation of estimated @var{x}; @var{mse} (k-by-1), the estimated
+## data error covariance scale factors (@math{\sigma^2}); and @var{S}
+## (p-by-p, or p-by-p-by-k if k > 1), the error covariance of @var{x}.
+##
+## Reference: Golub and Van Loan (1996), Matrix Computations (3rd Ed.), Johns Hopkins, Section 5.6.3
+##
+## @end deftypefn
+## @seealso{ols, gls, lsqnonneg}
+
+## Author: Nir Krakauer
+
+function [x, stdx, mse, S] = lscov (A, b, V = [], alg)
+
+  if (nargin < 2 || (rows (A) != rows (b)))
+    print_usage ();
+  endif
+  
+  n = rows (A);
+  p = columns (A);
+  k = columns (b);
+  
+  if (! isempty (V))
+    if (rows (V) != n || ! any (columns (V) == [1 n]))
+      error ("lscov: V should be a square matrix or a vector with the same number of rows as A");
+    endif
+    
+    if (isvector (V))
+      ## n-by-1 vector of inverse variances
+      v = diag (sqrt (V));
+      A = v * A;
+      b = v * b;
+    else
+      ## n-by-n covariance matrix
+      try
+        ## ordinarily V will be positive definite
+        B = chol (V)';
+      catch
+        ## if V is only positive semidefinite, use its
+        ## eigendecomposition to find a factor B such that V = B*B'
+        [B, lambda] = eig (V);
+        image_dims = (diag (lambda) > 0);
+        B = B(:, image_dims) * sqrt (lambda(image_dims, image_dims));
+      end_try_catch     
+      A = B \ A;
+      b = B \ b;
+    endif
+  endif
+  
+  pinv_A = pinv (A); #pseudoinverse
+
+  x = pinv_A * b;
+  
+  if (isargout (3))
+    dof = n - p; #degrees of freedom remaining after fit
+    SSE = sumsq (b - A * x);
+    mse = SSE / dof;
+  endif
+  
+  s = pinv_A * pinv_A';
+
+  stdx = sqrt (diag (s) * mse);
+  
+  if (isargout (4))
+    if (k == 1)
+      S = mse * s;
+    else
+      S = nan (p, p, k);
+      for i = 1:k
+        S(:, :, i) = mse(i) * s;
+      endfor
+    endif
+  endif
+endfunction
+
+%!test
+%! ## Longley data from the NIST Statistical Reference Dataset
+%! Z = [  60323    83.0   234289   2356     1590    107608  1947
+%!        61122    88.5   259426   2325     1456    108632  1948
+%!        60171    88.2   258054   3682     1616    109773  1949
+%!        61187    89.5   284599   3351     1650    110929  1950
+%!        63221    96.2   328975   2099     3099    112075  1951
+%!        63639    98.1   346999   1932     3594    113270  1952
+%!        64989    99.0   365385   1870     3547    115094  1953
+%!        63761   100.0   363112   3578     3350    116219  1954
+%!        66019   101.2   397469   2904     3048    117388  1955
+%!        67857   104.6   419180   2822     2857    118734  1956
+%!        68169   108.4   442769   2936     2798    120445  1957
+%!        66513   110.8   444546   4681     2637    121950  1958
+%!        68655   112.6   482704   3813     2552    123366  1959
+%!        69564   114.2   502601   3931     2514    125368  1960
+%!        69331   115.7   518173   4806     2572    127852  1961
+%!        70551   116.9   554894   4007     2827    130081  1962 ];
+%! ## Results certified by NIST using 500 digit arithmetic
+%! ## b and standard error in b
+%! V = [  -3482258.63459582         890420.383607373
+%!         15.0618722713733         84.9149257747669
+%!        -0.358191792925910E-01    0.334910077722432E-01
+%!        -2.02022980381683         0.488399681651699
+%!        -1.03322686717359         0.214274163161675
+%!        -0.511041056535807E-01    0.226073200069370
+%!         1829.15146461355         455.478499142212 ];
+%! rsd =  304.854073561965;
+%! y = Z(:,1); X = [ones(rows(Z),1), Z(:,2:end)];
+%! alpha = 0.05;
+%! [b, stdb, mse] = lscov (X, y);
+%! assert(b, V(:,1), 3e-6);
+%! assert(stdb, V(:,2), -1.e-5);
+%! assert(sqrt (mse), rsd, -1E-6);
+
+%!test
+%! ## Adapted from example in Matlab documentation
+%! x1 = [.2 .5 .6 .8 1.0 1.1]'; 
+%! x2 = [.1 .3 .4 .9 1.1 1.4]'; 
+%! X = [ones(size(x1)) x1 x2]; 
+%! y = [.17 .26 .28 .23 .27 .34]';
+%! [b, se_b, mse, S] = lscov(X, y);
+%! assert(b, [0.1203 0.3284 -0.1312]', 1E-4);
+%! assert(se_b, [0.0643 0.2267 0.1488]', 1E-4);
+%! assert(mse, 0.0015, 1E-4);
+%! assert(S, [0.0041 -0.0130 0.0075; -0.0130 0.0514 -0.0328; 0.0075 -0.0328 0.0221], 1E-4);
+%! w = [1 1 1 1 1 .1]'; 
+%! [bw, sew_b, msew] = lscov (X, y, w);
+%! assert(bw, [0.1046 0.4614 -0.2621]', 1E-4);
+%! assert(sew_b, [0.0309 0.1152 0.0814]', 1E-4);
+%! assert(msew, 3.4741e-004, -1E-4);
+%! V = .2*ones(length(x1)) + .8*diag(ones(size(x1)));
+%! [bg, sew_b, mseg] = lscov (X, y, V);
+%! assert(bg, [0.1203 0.3284 -0.1312]', 1E-4);
+%! assert(sew_b, [0.0672 0.2267 0.1488]', 1E-4);
+%! assert(mseg, 0.0019, 1E-4);
+%! y2 = [y 2*y];
+%! [b2, se_b2, mse2, S2] = lscov (X, y2);
+%! assert(b2, [b 2*b])
+%! assert(se_b2, [se_b 2*se_b])
+%! assert(mse2, [mse 4*mse])
+%! assert(S2(:, :, 1), S)
+%! assert(S2(:, :, 2), 4*S)
+
+%!test
+%! ## Artificial example with positive semidefinite weight matrix
+%! x = (0:0.2:2)';
+%! y = round(100*sin(x) + 200*cos(x));
+%! X = [ones(size(x)) sin(x) cos(x)];
+%! V = eye(numel(x));
+%! V(end, end-1) = V(end-1, end) = 1;
+%! [b, seb, mseb, S] = lscov (X, y, V);
+%! assert(b, [0 100 200]', 0.2);
--- a/scripts/statistics/base/module.mk	Sun Sep 07 11:30:41 2014 +0200
+++ b/scripts/statistics/base/module.mk	Mon Sep 08 08:09:45 2014 +0200
@@ -11,6 +11,7 @@
   statistics/base/kendall.m \
   statistics/base/kurtosis.m \
   statistics/base/logit.m \
+  statistics/base/lscov.m \
   statistics/base/mahalanobis.m \
   statistics/base/mean.m \
   statistics/base/meansq.m \