function stpwise(X,y,inmodel,alpha);
%  STPWISE Interactive tool for stpwise regression.
%   Stpwise(X,Y,INMODEL,ALPHA) fits a regression model of Y on the
%   columns of X specified in the vector INMODEL. ALPHA is the significance
%   for testing each term in the model. By default,
%   ALPHA = 1 - (1 - 0.025).^(1/p) where p is the number of columns in X.
%   This translates to plotted 95% simultaneous confidence intervals
%   (Bonferroni) for all the coefficients.
%
%   The least squares coefficient is plotted with a green filled circle.
%   A coefficient is not significantly different from zero if its confidence
%   interval crosses the white zero line. Significant model terms are plotted
%   using solid lines. Terms not significantly different from zero are plotted
%   with dotted lines.
%
%   Click on the confidence interval lines to toggle the state of the model
%   coefficients. If the confidence interval line is green the term 
%   is in the model.
%   If the the confidence interval line is red the term is not in the model.
%   Use the pop-up menu, Export, to move variables to the base workspace.

if ~isstr(X)
     action = 'start';
else
     action = X;
end

%On recursive calls get all necessary handles and data.
if ~strcmp(action,'start')
    flag = y;
    errorbar_fig = inmodel;
    table_fig = alpha(1);
    hist_fig = alpha(2);

    ch = get(0,'Children');
    good = find(ch == table_fig);
    if isempty(good)
       if ~isempty(errorbar_fig),close(errorbar_fig);end
       if ~isempty(hist_fig),close(hist_fig);end
       warndlg('Sorry, STPWISE requires all three figure windows to run.');
       return
    end

    good = find(ch == errorbar_fig);
    if isempty(good)
       if ~isempty(table_fig),close(table_fig);end
       if ~isempty(hist_fig),close(hist_fig);end
       warndlg('Sorry, STPWISE requires all three figure windows to run.');
       return
    end

    good = find(ch == hist_fig);
    if isempty(good)
       if ~isempty(table_fig),close(table_fig);end
       if ~isempty(errorbar_fig),close(errorbar_fig);end
       warndlg('Sorry, STPWISE requires all three figure windows to run.');
       return
    end

    figure_handles = [errorbar_fig table_fig hist_fig];
    histud = get(hist_fig,'UserData');
    u = get(errorbar_fig,'Userdata');

    X           = u.X;
    y           = u.y;
    inmodel     = u.inmodel;
    handles     = u.handles;
    bhandle     = u.bhandle;
    crit        = u.crit;
    outputpopup = u.outputpopup;
    scalebutton = u.scalebutton;
    instance    = u.instance;
    texthandle  = u.texthandle;
    [n, p] = size(X);
end

switch action

case 'start'
[n, p]=size(X);
colidx = 1:p;
% Argument Checks
if nargin < 3
   inmodel = colidx;
end

if nargin == 4
   sigprob = 1 - alpha/2;
else
   sigprob = (0.975).^(1/p);
end

% Monitor Size information.
screen = get(0,'ScreenSize');
screenht = screen(4);
screenwidth  = screen(3);

% Do initial statistical calculations.
mx = mean(X);
X = (X - mx(ones(n,1),:));
y = y - mean(y);
sx = std(X);
scaledx = X./sx(ones(n,1),:);

df = n-2:-1:n-p-1;
crit = tinv(sigprob,df);
[beta, delta, tstats, stats,sse] = FitModel(X,y,inmodel,crit);

% Create the three windows for the Stpwise GUI
table_fig = figure('Visible','off');
hist_fig = figure('Visible','off');
whitebg(hist_fig,[0 0 0]);
instance = length(findobj(0,'Tag','stepfig'))+1;
drawnow;
errorbar_fig = figure('Visible','off');
whitebg(errorbar_fig,[0 0 0]);
figure_handles = [errorbar_fig table_fig hist_fig];

% Set Up for Stpwise Plot Figure
u = MakeErrorbarFigure(figure_handles,p,instance,screenht);
u.texthandle = [];
u.X          = X;
u.y          = y;
u.inmodel    = inmodel;
u.crit       = crit;
u.scaledx    = scaledx;

yref = get(gca,'YLim');
plot([0 0],yref,'w-');

% Make coefficients plot with error bars
handles = plot([(beta-delta)'; (beta+delta)'],[colidx; colidx]);
for k = 1:length(colidx)
    bhandle(k,1) = plot(beta(k),colidx(k),'.');
    parens =[int2str(k),',',int2str(errorbar_fig),',[',int2str(table_fig),' ',int2str(hist_fig),'])'];
  	set(bhandle(k,1),'ButtonDownFcn',['stpwise(''click'',',parens],'MarkerSize',20)
    set(handles(k),'ButtonDownFcn',['stpwise(''click'',',parens],'LineWidth',2)
end
u.handles   = handles;
u.bhandle   = bhandle;
u.instance  = instance;
notin = colidx;
notin(inmodel) = [];
UpdateCoefficientsPlot(beta,delta,inmodel,notin,handles,bhandle)

% Set Up for Stpwise Parameter Data Table.
MakeTableFigure(figure_handles,instance,p,screenht)
WriteDataTable(beta,delta,p,figure_handles,inmodel,stats)

% Set Up for History Figure
MakeHistoryFigure(inmodel,n,p,instance,stats,figure_handles);

parens = ['[]',',',int2str(errorbar_fig),',[',int2str(table_fig),' ',int2str(hist_fig),'])'];
set(errorbar_fig,'WindowButtonMotionFcn',['stpwise(''stepmotion'',',parens])
set(table_fig,'WindowButtonMotionFcn',['stpwise(''datamotion'',',parens])

set(hist_fig,'Visible','on','HandleVisibility','callback');
set(table_fig,'Visible','on','HandleVisibility','callback');
set(errorbar_fig,'Userdata',u,'Visible','on','HandleVisibility','callback');
% End of initialization Phase

% Callback for motion inside the Coefficients Table figure.
case 'datamotion',
      set(0,'CurrentFigure',table_fig);
       cursorstate = get(table_fig,'Pointer');
      ax = findobj(table_fig,'Type','axes');
       cp = get(ax,'CurrentPoint');
       cx = cp(1,1);
       cy = cp(1,2);
      pos = get(table_fig,'Position');
      if 80 < cx & 130 > cx & 45 < cy & pos(4)-30 > cy
          online = 1;
      else
         online = 0;
      end
       if online & strcmp(cursorstate,'arrow'),
          set(gcf,'Pointer','circle');
       elseif ~online & strcmp(cursorstate,'circle'),
          set(gcf,'Pointer','arrow');
       end

% Callback for motion inside the Stpwise Errorbar Graph figure.
case 'stepmotion',
      figure(errorbar_fig);
      cursorstate = get(errorbar_fig,'Pointer');
      cp = get(gca,'CurrentPoint');
      cx = cp(1,1);
      cy = cp(1,2);
      if cy > 0.9 & cy < length(handles)+0.1
         xint = get(handles(round(cy)),'XData');
      else
         xint = zeros(1,2);
      end
      if abs(cy-round(cy)) < 0.1 & cx > xint(1) & cx < xint(2)
          online = 1;
      else
         online = 0;
      end
       if online & strcmp(cursorstate,'arrow'),
          set(gcf,'Pointer','circle');
       elseif ~online & strcmp(cursorstate,'circle'),
          set(gcf,'Pointer','arrow');
       end

% Callback for motion inside the Stpwise History figure.
case 'histmotion',
      cursorstate = get(hist_fig,'Pointer');
      set(0,'CurrentFigure',hist_fig);
      cp = get(gca,'CurrentPoint');
      cx = cp(1,1);
      if abs(cx-round(cx)) < 0.02 & round(cx) > 1
          online = 1;
      else
          online = 0;
      end
      if online & strcmp(cursorstate,'arrow'),
          set(gcf,'Pointer','circle');
      elseif ~online & strcmp(cursorstate,'circle'),
          set(gcf,'Pointer','arrow');
      end
 
% Callback for Export Button.
case 'output',
     bmf = get(errorbar_fig,'WindowButtonMotionFcn');
     bdf = get(errorbar_fig,'WindowButtonDownFcn');
     set(errorbar_fig,'WindowButtonMotionFcn','');
     set(errorbar_fig,'WindowButtonDownFcn','');

     outval = get(outputpopup,'Value');
     switch outval
        case 1,
           return,
        case 2,
           promptstr = 'Enter names for the parameters or use the supplied default.';
           entrystr = 'beta';
        case 3,
           promptstr = 'Enter names for the confidence intervals or use the supplied default.';
           entrystr = 'betaci';
        case 4,
           promptstr = 'Enter names for the terms in the model or use the supplied default.';
           entrystr = 'in';
        case 5,
           promptstr = 'Enter names for the terms out of the model or use the supplied default.';
           entrystr = 'out';
        case 6,
           promptstr = 'Enter names for statistical outputs or use the defaults.';
           entrystr = 'beta,betaci,in,out,sse';
        end

    dlghandle = dialog('Visible','off','WindowStyle','modal');

    set(dlghandle,'Units','pixels','Position',[100 300 400 100],'Visible','on');
    uicontrol(dlghandle,'Style','text','Units','pixels',...
           'Position',[10 75 380 20],...
           'String',promptstr);

    u.texthandle = uicontrol(dlghandle,'Style','edit','Units','pixels',...
                'String',entrystr,'HorizontalAlignment','center',...
                'Position',[50 40 300 20]);
    parens = ['[],',int2str(errorbar_fig),',[',int2str(table_fig),' ',int2str(hist_fig),'])'];
    ok_button = uicontrol('Style','Pushbutton','Units','pixels','Position',[180 5 40 20],...
                'Callback',['stpwise(''toworkspace'',' parens ';close(gcbf)'],...
                'String','OK');

   set(dlghandle,'HandleVisibility','off')
   set(errorbar_fig,'UserData',u);
   set(errorbar_fig,'WindowButtonMotionFcn',bmf);
   set(errorbar_fig,'WindowButtonDownFcn',bdf);

case 'toworkspace',
    if get(scalebutton,'Value') == 1
       X = u.scaledx;
    end
 
     [beta, delta, tstats, stats,sse] = FitModel(X,y,inmodel,crit);
	notin = 1:p;
	notin(inmodel) = [];

     outval = get(outputpopup,'Value');

     s = get(texthandle,'String');
 
     switch outval
        case 1,
           return,
        case 2,
	      assignin('base',s,beta);
        case 3,
	      assignin('base',s,[beta-delta beta+delta]);
        case 4,
	      assignin('base',s,inmodel);
        case 5,
	      assignin('base',s,notin);
        case 6,
           cpos=findstr(s,',');
	      assignin('base',s(1:cpos(1)-1),beta);
	      assignin('base',s((cpos(1)+1):(cpos(2)-1)),[beta-delta beta+delta]);
	      assignin('base',s((cpos(2)+1):(cpos(3)-1)),inmodel);
		  assignin('caller',s((cpos(2)+1):(cpos(3)-1)),inmodel);
	      assignin('base',s((cpos(3)+1):(cpos(4)-1)),notin);
		  assignin('base',s((cpos(4)+1):end),sse);
		  assignin('caller',s((cpos(4)+1):end),sse);
     end
     set(outputpopup,'Value',1);

case 'click'
    cf = get(0,'CurrentFigure');
    figure(errorbar_fig);
    toggle = any(inmodel == flag);
    if toggle == 0
       u.inmodel = sort([inmodel(:); flag]);
    else
       k = find(inmodel==flag);
       u.inmodel(k) = [];
    end
    inmodel = u.inmodel;
    if get(scalebutton,'Value') == 1
       X = u.scaledx;
    end

    [beta, delta, tstats, stats, sse] = FitModel(X,y,inmodel,crit);
    notin = 1:p;
    notin(inmodel) = [];
    UpdateCoefficientsPlot(beta,delta,inmodel,notin,handles,bhandle)
    set(errorbar_fig,'UserData',u);

    figure(table_fig);
    ch = findobj(table_fig,'Tag','text');
    delete(ch);
    WriteDataTable(beta,delta,p,figure_handles,inmodel,stats)
 
    figure(hist_fig);
    UpdateHistoryPlot(stats,inmodel,n,p,histud,figure_handles)
    figure(cf);

% Callback for Scale Inputs radio button.
case 'scale',
    if get(scalebutton,'Value') == 1
       X = u.scaledx;
    end
    [beta, delta, tstats, stats, sse] = FitModel(X,y,inmodel,crit);
    notin = 1:p;
    notin(inmodel) = [];
    UpdateCoefficientsPlot(beta,delta,inmodel,notin,handles,bhandle)
 
    figure(table_fig);
    ch = findobj(table_fig,'Tag','text');
    delete(ch);
    WriteDataTable(beta,delta,p,figure_handles,inmodel,stats)
 
    figure(errorbar_fig);

case 'history',
    in = histud.instore;
    in = in(:,flag);
    in = in(find(~isnan(in)));
    set(hist_fig,'Pointer','watch');
    stpwise(X,y,in)
    set(hist_fig,'Pointer','arrow');
 
case 'close',
    close(table_fig);
    close(errorbar_fig);
    close(hist_fig);

case 'help',
dohelp;

end

function [beta, delta, tstats, stats, sse] = FitModel(X,y,inmodel,crit);
% Local function for fitting stpwise regression model.
[n, p] = size(X);
colidx = 1:p;
notin  = colidx;
notin(inmodel) = [];

if ~isempty(inmodel)
    [Q,R]=qr(X(:,inmodel),0);
    b = R\(Q'*y);
    r = y - X(:,inmodel)*b;
    RI = R\eye(size(R));
    xtxid = (sum(RI'.*RI'))';
else
    r = y;
end
terms = length(inmodel);
mse = r'*r./(n-terms-1);
sse=mse*(n-terms-1);
rmse = sqrt(mse);
tss = y'*y;
rss = y'*y-r'*r;
if terms == 0
    prob = 1;
    r2   = 0;
    f    = 0;
else
    f   = (rss./terms)./mse;
    prob = 1-fcdf(f,terms,(n-terms-1));
    r2  = rss./tss;
    seb = sqrt(xtxid)*rmse;
    t = b./seb;
end

beta = zeros(p,1);
tstats = zeros(p,1);
delta = zeros(p,1);
if ~isempty(inmodel)
    delta(inmodel) = seb*crit(terms);
    beta(inmodel) = b;
    tstats(inmodel) = t;
end


for index = notin
    Xnew = [X(:,inmodel) X(:,index)];
    [Qadd, Radd] = qr(Xnew,0);
    bnew = Radd\(Qadd'*y);
    rnew = y - Xnew*bnew;
    RInew = Radd\eye(terms+1,terms+1);
    xtxidnew = (sum(RInew'.*RInew'))';
    rmse1 = sqrt(sum(rnew.*rnew)./(n-terms-2));
    seb = sqrt(xtxidnew(terms+1))*rmse1;

    beta(index) = bnew(terms+1);
    tstats(index) = bnew(terms+1)./seb;
    delta(index) = seb*crit(terms+1);
end
stats = [rmse r2 f prob];

function u = MakeErrorbarFigure(figure_handles,p,instance,screenht)
% Local function for creating Errorbar Plot Figure and its Uicontrols.

errorbar_fig = figure_handles(1);
stepht = min(50*(p+1),480);
set(errorbar_fig,'Units','Pixels','Tag','stepfig',...
    'Position',[5+30*(instance-1) screenht-stepht-30*instance-50 300 stepht],'Resize','off',...
    'Name',['Stpwise Plot #',int2str(instance)]);

figpos  = get(errorbar_fig,'Position');
step_axes = axes;
set(step_axes,'NextPlot','add','DrawMode','fast','Units','Pixels',  ...
     'Tag','stepaxes','Box','on','Ydir','reverse','Ylim',[0.5 p+0.5], ...
	'Ytick',(1:p),'Position',[30 70 figpos(3)-40 figpos(4)-90],'FontSize',9,'FontName','Geneva');

parens = ['[],',int2str(errorbar_fig),',[',int2str(figure_handles(2)),' ',int2str(figure_handles(3)),'])'];
u.outputpopup = uicontrol(errorbar_fig,'Style','Popup','String',...
   		'Export|Parameters|Confidence Intervals|Terms In|Terms Out|All','Value',1,...
         'Units','Pixels','Position',[190 10 100 20],...
         'CallBack',['stpwise(''output'',',parens]);

u.scalebutton = uicontrol(errorbar_fig,'Style','radio','String',...
         'Scale Inputs','Units','Pixels','Position',[100 10 80 20],...
         'CallBack',['stpwise(''scale'',',parens]);

close_button = uicontrol('Style','Pushbutton','Units','Pixels','String','Close',...
                'Position',[30 10 60 20],'Callback',['stpwise(''close'',',parens]);

xl = xlabel('Coefficients with Error Bars','Color','w');
yl = ylabel('Model Term Number');
set(xl,'FontSize',10,'FontName','Geneva');
set(yl,'FontSize',10,'FontName','Geneva');

function UpdateCoefficientsPlot(beta,delta,inmodel,notin,handles,bhandle)
% Local function for plotting coefficients with error bars.
    p = length(beta);
    for k = 1:p
       set(handles(k),'XData',[beta(k)-delta(k); beta(k)+delta(k)]);
       set(bhandle(k),'XData',beta(k));
    end
    xmax = max(beta+delta);
    xmin = min(beta-delta);
    xrange = xmax-xmin;
    set(gca,'XLim',[xmin-0.05*xrange xmax+0.05*xrange]);

    notsig = find(beta-delta<0 & beta+delta>0);
    sig = 1:p;
    sig(notsig) = [];
    set(handles(inmodel),'Color','g');
    set(bhandle(inmodel),'Color','g');

    set(handles(notin),'Color','r');
    set(bhandle(notin),'Color','r');

    set(handles(sig),'LineStyle','-');
    set(handles(notsig),'LineStyle',':');

function MakeTableFigure(figure_handles,instance,p,screenht)
% Local function for creating Parameters Table Figure and its Uicontrols.

table_fig = figure_handles(2);
fight = p*12 + 90;
figure(table_fig);
set(table_fig,'Units','Pixels',...
    'Position',[290+30*instance screenht-(fight+30*instance)-50 340 fight],'Color','k', ...
    'Name',['Stpwise Table #',int2str(instance)],'Tag','datafig','Resize','off');
ax = axes;
set(ax,'Units','Pixels','Position',[10 25 380 fight-25],'Color','k',...
     'Xlim',[0 340],'Ylim',[0 fight-25],'Visible','off');

parens = ['[],',int2str(figure_handles(1)),',[',int2str(table_fig),' ',int2str(figure_handles(3)),'])'];
uicontrol('Style','Pushbutton','Units','Pixels','String','Close', ...
           'Position',[10 5 100 20],'Callback',['stpwise(''close'',',parens]);

uicontrol('Style','Pushbutton','Units','Pixels','Position',[230 5 100 20],...
           'Callback',['stpwise(''help'',',parens],'String','Help');

function WriteDataTable(beta,delta,p,figure_handles,inmodel,stats)
% Local function for writing out all the entries in the Parameter Data Table.

fight = p*12 + 90;
h=text(180,fight-32,'Confidence Intervals');
set(h,'FontName','Geneva','FontSize',9,'Color','w');
colheads = str2mat('Column #','Parameter','Lower ','Upper');
colheads1 = str2mat('RMSE','R-square','F','P');
z = [10 80 175 245];
z1 = [10 80 195 265];
h = zeros(4,1);
l = zeros(4,1);
for k = 1:4
   h(k)=text(z(k),fight-45,colheads(k,:));
   set(h(k),'FontName','Geneva','FontSize',9,'Color','w');
   l(k)=text(z1(k),20,colheads1(k,:));
   set(l(k),'FontName','Geneva','FontSize',9,'Color','w');
end

x = fight-50;
h = zeros(4,p+1);
for params = 1:p
     z = [30 120 200 270];
     x = x - 12;
     row = [params beta(params) beta(params)-delta(params) beta(params)+delta(params)];
     parens = [int2str(params),',',int2str(figure_handles(1)),',[',int2str(figure_handles(2)),' ',int2str(figure_handles(3)),'])'];
     bdf = ['stpwise(''click'',',parens];
     for k = 1:4
        if k == 1,
           h(k,params) = text(z(k),x,sprintf('%4i',row(k)));
           set(h(k,params),'HorizontalAlignment','right',...
              'FontName','Geneva','FontSize',9,'Tag','text',...
              'ButtonDownFcn',bdf);
        else
           h(k,params) = text(z(k),x,sprintf('%11.4g',row(k)));
           set(h(k,params),'HorizontalAlignment','right','Tag','text',...
              'FontName','Geneva','FontSize',9,'ButtonDownFcn',bdf);
        end
        if any(inmodel == params)
          set(h(k,params),'Color','g');
        else
          set(h(k,params),'Color','r');
        end
    end
    z = [35 120 205 290];
    for k = 1:4
        h(k,p+1) = text(z(k),6,sprintf('%11.4g',stats(k)));
        set(h(k,p+1),'HorizontalAlignment','right','Tag','text',...
          'FontName','Geneva','FontSize',9,'Color','w');
    end
end

function MakeHistoryFigure(inmodel,n,p,instance,stats,figure_handles)
% Local function for creating Stpwise History Figure.
screen = get(0,'ScreenSize');
screenht = screen(4);
screenwidth  = screen(3);
fight = p*12 + 90;
hist_fig = figure_handles(3);
parens = ['[]',',',int2str(figure_handles(1)),',[',int2str(figure_handles(2)),' ',int2str(hist_fig),'])'];
if screenwidth > 970
    set(hist_fig,'WindowButtonMotionFcn',['stpwise(''histmotion'',',parens],...
      'Units','Pixels','Position',[670 screenht-280 300 200]);
else
    set(hist_fig,'WindowButtonMotionFcn',['stpwise(''histmotion'',',parens],...
      'Units','Pixels','Position',[290+30*instance screenht-(fight+30*instance)-270 300 120]);
end
set(hist_fig,'Tag','histfig','Name',['Stpwise History #',int2str(instance)]);

trm  = n-1:-1:n-p-1;
trml = length(trm);
low  = 0.025;
hi   = 0.975;

histud.chi2crit = chi2inv([low(ones(trml,1),1) hi(ones(trml,1),1)],[trm' trm']);
figure(figure_handles(3));
UpdateHistoryPlot(stats,inmodel,n,p,histud,figure_handles);
xlabel('Model Number');
ylabel('RMSE');

function UpdateHistoryPlot(stats,inmodel,n,p,histud,figure_handles)
% Local function for adding new rmse error bar to History Plot.
rmse = stats(1);
mse = rmse*rmse;
terms = length(inmodel);
rmseci  =  sqrt([(mse*sqrt((n-terms-1)./histud.chi2crit(terms+1,2))) ...
                  (mse*sqrt((n-terms-1)./histud.chi2crit(terms+1,1)))]);

sse=mse*(n-terms-1);
cirange = diff(rmseci);
ylhi = rmseci(2) + 0.1*cirange;
yllo = rmseci(1) - 0.1*cirange;

tmp = NaN;
tmp = tmp(ones(p,1),1);
tmp(1:terms) = inmodel;

if length(fieldnames(histud)) < 3
    histud.instore = tmp;
    num_mod = 1;
else
    in = histud.instore;
    in = [in tmp];
    histud.instore = in;
    num_mod = length(histud.rmsehandle)+1;
end
histud.rmsehandle(num_mod) = plot([num_mod num_mod],rmseci);
 
yl = get(gca,'Ylim');
yhi = max(ylhi,yl(2));
ylo = min(yllo,yl(1));
set(gca,'Xlim',[0.5 num_mod+0.5],'Xtick',(1:num_mod),'Ylim',[ylo yhi], ...
     'Position',[0.15 0.15 0.8 0.8],'NextPlot','add');
rmsedothndl = plot(num_mod,rmse,'.');

parens = [int2str(num_mod),',',int2str(figure_handles(1)),',[', ...
           int2str(figure_handles(2)),' ',int2str(figure_handles(3)),'])'];
bdf = ['stpwise(''history'',',parens];
set(histud.rmsehandle(num_mod),'ButtonDownFcn',bdf);
set(rmsedothndl,'MarkerSize',20,'ButtonDownFcn',bdf);
set(figure_handles(3),'UserData',histud);

function dohelp
str{1,1} = 'Stpwise Regression';
str{1,2} = {
'Stpwise Regression Interactive Graphic User Interface'
' '
'The interface consists of three interactively linked figure windows:'
'   o The Stpwise Regression Plot'
'   o The Stpwise Regression Diagnostics Table'
'   o The Stpwise History'
' '
'All three windows have hot regions. When your mouse is above'
'one of these regions, the pointer changes from an arrow to a circle.'
'Mousing down at this point initiates some activity in the interface.'
' '
'To understand how to use a given window choose one of the items'
'from the popup menu labelled Topics above.'
};

str{2,1} = 'Stpwise Plot';
str{2,2} = {
'Stpwise Regression Plot'
' '
'Coefficients and Confidence Intervals'
' '
'This plot shows the regression coefficient and confidence interval for every'
'term (in or out of the model.) The green lines represent terms in the model'
'while red lines indicate that the term is not currently in the model.'
' '
'Statistically significant terms are solid lines. Dotted lines show that '
'the fitted coefficient is not significantly different from zero.'
' '
'Clicking on a line in this plot toggles its state. That is, a term in the'
'model (green line) gets removed (turns red), and terms out of the model'
'(red line) enter the model (turn green).'
' '
'The coefficient for a term out of the model is the coefficient resulting from'
'adding that term to the current model.'
' '
'Scale Inputs'
'Pressing the button labeled Scale Inputs centers and normalizes the columns'
'of the input matrix to have a standard deviation of one.'
' '
'Export'
'This popup menu allows you to export variables from the stpwise function to'
'the base workspace.'
' '
'Close'
'The Close button removes all the figure windows.'
};

str{3,1} = 'Stpwise Diagnostics';
str{3,2} = {
'Stpwise Regression Diagnostics Table'
' '
'Coefficients and Confidence Intervals'
'The table at the top of the figure shows the regression coefficient and '
'confidence interval for every term (in or out of the model.) The green rows'
'in the table represent terms in the model while red rows indicate terms not'
'currently in the model.'
' '
'Clicking on a row in this table toggles the state of the corresponding term.'
'That is, a term in the model (green row) gets removed (turns red), and terms'
'out of the model (red rows) enter the model (turn green).'
' '
'The coefficient for a term out of the model is the coefficient resulting from'
'adding that term to the current model.'
' '
'Additional Diagnostic Statistics'
'There are also several diagnostic statistics at the bottom of the table:'
'   o RMSE - the root mean squared error of the current model.'
'   o R-square - the amount of response variability explained by the model.'
'   o F - the overall F statistic for the regression.'
'   o P - the associated significance probability.'
' '
'Close Button'
'Shuts down all windows.'
' '
'Help Button'
'Activates on-line help.'
};

str{4,1} = 'Stpwise History';
str{4,2} = {
'Stpwise History'
' '
'Description'
'This plot shows the RMSE and a confidence interval for every model generated'
'in the course of the interactive use of the other windows. '
' '
'Recreating a Previous Model'
'Clicking on one of these lines will re-create the current model at that point'
'in the analysis using a NEW set of windows. You can thus compare the two'
'candidate models directly.'
};

for k = 1:4,
     str{k,2} = char(str{k,2});
end
helpwin(str,'Stpwise Regression','Stpwise Regression Help')