diff --git a/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.lfm b/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.lfm
index 49fa5fdd1..04ed87d9d 100644
--- a/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.lfm
+++ b/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.lfm
@@ -1,236 +1,181 @@
-object SignTestFrm: TSignTestFrm
+inherited SignTestFrm: TSignTestFrm
   Left = 550
-  Height = 372
+  Height = 345
   Top = 297
-  Width = 391
-  AutoSize = True
+  Width = 382
   Caption = 'The Matched Pairs Sign Test'
-  ClientHeight = 372
-  ClientWidth = 391
-  OnActivate = FormActivate
-  OnCreate = FormCreate
-  OnShow = FormShow
-  LCLVersion = '2.1.0.0'
-  object Label1: TLabel
-    AnchorSideLeft.Control = Owner
-    AnchorSideTop.Control = Owner
-    Left = 8
-    Height = 15
-    Top = 8
-    Width = 97
-    BorderSpacing.Left = 8
-    BorderSpacing.Top = 8
-    Caption = 'Variables Available'
-    ParentColor = False
+  ClientHeight = 345
+  ClientWidth = 382
+  inherited ParamsPanel: TPanel
+    Height = 329
+    ClientHeight = 329
+    inherited CloseBtn: TButton
+      Top = 304
+    end
+    inherited ComputeBtn: TButton
+      Top = 304
+    end
+    inherited ResetBtn: TButton
+      Top = 304
+    end
+    inherited HelpBtn: TButton
+      Top = 304
+    end
+    inherited ButtonBevel: TBevel
+      Top = 288
+    end
+    object Label1: TLabel[5]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideTop.Control = ParamsPanel
+      Left = 0
+      Height = 15
+      Top = 0
+      Width = 100
+      Caption = 'Available Variables:'
+      ParentColor = False
+    end
+    object Label2: TLabel[6]
+      AnchorSideLeft.Control = Var1Edit
+      AnchorSideBottom.Control = Var1Edit
+      Left = 166
+      Height = 15
+      Top = 21
+      Width = 50
+      Anchors = [akLeft, akBottom]
+      BorderSpacing.Bottom = 2
+      Caption = 'Variable 1'
+      ParentColor = False
+    end
+    object Label3: TLabel[7]
+      AnchorSideLeft.Control = Var2Edit
+      AnchorSideBottom.Control = Var2Edit
+      Left = 166
+      Height = 15
+      Top = 109
+      Width = 50
+      Anchors = [akLeft, akBottom]
+      BorderSpacing.Bottom = 2
+      Caption = 'Variable 2'
+      ParentColor = False
+    end
+    object VarList: TListBox[8]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideTop.Control = Label1
+      AnchorSideTop.Side = asrBottom
+      AnchorSideRight.Control = Var1In
+      AnchorSideBottom.Control = ButtonBevel
+      Left = 0
+      Height = 271
+      Top = 17
+      Width = 126
+      Anchors = [akTop, akLeft, akRight, akBottom]
+      BorderSpacing.Top = 2
+      BorderSpacing.Right = 6
+      ItemHeight = 0
+      OnDblClick = VarListDblClick
+      OnSelectionChange = VarListSelectionChange
+      TabOrder = 4
+    end
+    object Var1In: TBitBtn[9]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideLeft.Side = asrCenter
+      AnchorSideTop.Control = VarList
+      Left = 132
+      Height = 26
+      Top = 17
+      Width = 26
+      Images = MainDataModule.ImageList
+      ImageIndex = 1
+      OnClick = Var1InClick
+      Spacing = 0
+      TabOrder = 5
+    end
+    object Var1Out: TBitBtn[10]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideLeft.Side = asrCenter
+      AnchorSideTop.Control = Var1In
+      AnchorSideTop.Side = asrBottom
+      Left = 132
+      Height = 26
+      Top = 47
+      Width = 26
+      BorderSpacing.Top = 4
+      Images = MainDataModule.ImageList
+      ImageIndex = 0
+      OnClick = Var1OutClick
+      Spacing = 0
+      TabOrder = 6
+    end
+    object Var2In: TBitBtn[11]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideLeft.Side = asrCenter
+      AnchorSideTop.Control = Var1Out
+      AnchorSideTop.Side = asrBottom
+      Left = 132
+      Height = 26
+      Top = 105
+      Width = 26
+      BorderSpacing.Top = 32
+      Images = MainDataModule.ImageList
+      ImageIndex = 1
+      OnClick = Var2InClick
+      Spacing = 0
+      TabOrder = 7
+    end
+    object Var2Out: TBitBtn[12]
+      AnchorSideLeft.Control = ParamsPanel
+      AnchorSideLeft.Side = asrCenter
+      AnchorSideTop.Control = Var2In
+      AnchorSideTop.Side = asrBottom
+      Left = 132
+      Height = 26
+      Top = 135
+      Width = 26
+      BorderSpacing.Top = 4
+      Images = MainDataModule.ImageList
+      ImageIndex = 0
+      OnClick = Var2OutClick
+      Spacing = 0
+      TabOrder = 8
+    end
+    object Var1Edit: TEdit[13]
+      AnchorSideLeft.Control = Var1In
+      AnchorSideLeft.Side = asrBottom
+      AnchorSideRight.Control = ParamsPanel
+      AnchorSideRight.Side = asrBottom
+      AnchorSideBottom.Control = Var1Out
+      AnchorSideBottom.Side = asrBottom
+      Left = 166
+      Height = 23
+      Top = 38
+      Width = 125
+      Anchors = [akLeft, akRight, akBottom]
+      BorderSpacing.Left = 8
+      BorderSpacing.Bottom = 12
+      ReadOnly = True
+      TabOrder = 9
+      Text = 'Var1Edit'
+    end
+    object Var2Edit: TEdit[14]
+      AnchorSideLeft.Control = Var2In
+      AnchorSideLeft.Side = asrBottom
+      AnchorSideRight.Control = ParamsPanel
+      AnchorSideRight.Side = asrBottom
+      AnchorSideBottom.Control = Var2Out
+      AnchorSideBottom.Side = asrBottom
+      Left = 166
+      Height = 23
+      Top = 126
+      Width = 125
+      Anchors = [akLeft, akRight, akBottom]
+      BorderSpacing.Left = 8
+      BorderSpacing.Bottom = 12
+      ReadOnly = True
+      TabOrder = 10
+      Text = 'Var2Edit'
+    end
   end
-  object Label2: TLabel
-    AnchorSideLeft.Control = Var1Edit
-    AnchorSideBottom.Control = Var1Edit
-    Left = 217
-    Height = 15
-    Top = 33
-    Width = 50
-    Anchors = [akLeft, akBottom]
-    BorderSpacing.Bottom = 2
-    Caption = 'Variable 1'
-    ParentColor = False
-  end
-  object Label3: TLabel
-    AnchorSideLeft.Control = Var2Edit
-    AnchorSideBottom.Control = Var2Edit
-    Left = 217
-    Height = 15
-    Top = 125
-    Width = 50
-    Anchors = [akLeft, akBottom]
-    BorderSpacing.Bottom = 2
-    Caption = 'Variable 2'
-    ParentColor = False
-  end
-  object VarList: TListBox
-    AnchorSideLeft.Control = Owner
-    AnchorSideTop.Control = Label1
-    AnchorSideTop.Side = asrBottom
-    AnchorSideRight.Control = Var1In
-    AnchorSideBottom.Control = Bevel1
-    Left = 8
-    Height = 298
-    Top = 25
-    Width = 165
-    Anchors = [akTop, akLeft, akRight, akBottom]
-    BorderSpacing.Left = 8
-    BorderSpacing.Top = 2
-    BorderSpacing.Right = 8
-    Constraints.MinHeight = 200
-    ItemHeight = 0
-    OnSelectionChange = VarListSelectionChange
-    TabOrder = 0
-  end
-  object Var1In: TBitBtn
-    AnchorSideLeft.Control = Owner
-    AnchorSideLeft.Side = asrCenter
-    AnchorSideTop.Control = VarList
-    Left = 181
-    Height = 28
-    Top = 25
-    Width = 28
-    Images = MainDataModule.ImageList
-    ImageIndex = 1
-    OnClick = Var1InClick
-    Spacing = 0
-    TabOrder = 1
-  end
-  object Var1Out: TBitBtn
-    AnchorSideLeft.Control = Owner
-    AnchorSideLeft.Side = asrCenter
-    AnchorSideTop.Control = Var1In
-    AnchorSideTop.Side = asrBottom
-    Left = 181
-    Height = 28
-    Top = 57
-    Width = 28
-    BorderSpacing.Top = 4
-    Images = MainDataModule.ImageList
-    ImageIndex = 0
-    OnClick = Var1OutClick
-    Spacing = 0
-    TabOrder = 2
-  end
-  object Var2In: TBitBtn
-    AnchorSideLeft.Control = Owner
-    AnchorSideLeft.Side = asrCenter
-    AnchorSideTop.Control = Var1Out
-    AnchorSideTop.Side = asrBottom
-    Left = 181
-    Height = 28
-    Top = 117
-    Width = 28
-    BorderSpacing.Top = 32
-    Images = MainDataModule.ImageList
-    ImageIndex = 1
-    OnClick = Var2InClick
-    Spacing = 0
-    TabOrder = 4
-  end
-  object Var2Out: TBitBtn
-    AnchorSideLeft.Control = Owner
-    AnchorSideLeft.Side = asrCenter
-    AnchorSideTop.Control = Var2In
-    AnchorSideTop.Side = asrBottom
-    Left = 181
-    Height = 28
-    Top = 149
-    Width = 28
-    BorderSpacing.Top = 4
-    Images = MainDataModule.ImageList
-    ImageIndex = 0
-    OnClick = Var2OutClick
-    Spacing = 0
-    TabOrder = 5
-  end
-  object Var1Edit: TEdit
-    AnchorSideLeft.Control = Var1In
-    AnchorSideLeft.Side = asrBottom
-    AnchorSideRight.Control = Owner
-    AnchorSideRight.Side = asrBottom
-    AnchorSideBottom.Control = Var1Out
-    AnchorSideBottom.Side = asrBottom
-    Left = 217
-    Height = 23
-    Top = 50
-    Width = 166
-    Anchors = [akLeft, akRight, akBottom]
-    BorderSpacing.Left = 8
-    BorderSpacing.Right = 8
-    BorderSpacing.Bottom = 12
-    ReadOnly = True
-    TabOrder = 3
-    Text = 'Var1Edit'
-  end
-  object Var2Edit: TEdit
-    AnchorSideLeft.Control = Var2In
-    AnchorSideLeft.Side = asrBottom
-    AnchorSideRight.Control = Owner
-    AnchorSideRight.Side = asrBottom
-    AnchorSideBottom.Control = Var2Out
-    AnchorSideBottom.Side = asrBottom
-    Left = 217
-    Height = 23
-    Top = 142
-    Width = 166
-    Anchors = [akLeft, akRight, akBottom]
-    BorderSpacing.Left = 8
-    BorderSpacing.Right = 8
-    BorderSpacing.Bottom = 12
-    ReadOnly = True
-    TabOrder = 6
-    Text = 'Var2Edit'
-  end
-  object ResetBtn: TButton
-    AnchorSideRight.Control = ComputeBtn
-    AnchorSideBottom.Control = Owner
-    AnchorSideBottom.Side = asrBottom
-    Left = 182
-    Height = 25
-    Top = 339
-    Width = 54
-    Anchors = [akRight, akBottom]
-    AutoSize = True
-    BorderSpacing.Left = 8
-    BorderSpacing.Top = 8
-    BorderSpacing.Right = 8
-    BorderSpacing.Bottom = 8
-    Caption = 'Reset'
-    OnClick = ResetBtnClick
-    TabOrder = 7
-  end
-  object ComputeBtn: TButton
-    AnchorSideRight.Control = CloseBtn
-    AnchorSideBottom.Control = Owner
-    AnchorSideBottom.Side = asrBottom
-    Left = 244
-    Height = 25
-    Top = 339
-    Width = 76
-    Anchors = [akRight, akBottom]
-    AutoSize = True
-    BorderSpacing.Left = 8
-    BorderSpacing.Top = 8
-    BorderSpacing.Right = 8
-    BorderSpacing.Bottom = 8
-    Caption = 'Compute'
-    OnClick = ComputeBtnClick
-    TabOrder = 8
-  end
-  object CloseBtn: TButton
-    AnchorSideRight.Control = Owner
-    AnchorSideRight.Side = asrBottom
-    AnchorSideBottom.Control = Owner
-    AnchorSideBottom.Side = asrBottom
-    Left = 328
-    Height = 25
-    Top = 339
-    Width = 55
-    Anchors = [akRight, akBottom]
-    AutoSize = True
-    BorderSpacing.Left = 8
-    BorderSpacing.Top = 8
-    BorderSpacing.Right = 8
-    BorderSpacing.Bottom = 8
-    Caption = 'Close'
-    ModalResult = 11
-    TabOrder = 9
-  end
-  object Bevel1: TBevel
-    AnchorSideLeft.Control = Owner
-    AnchorSideRight.Control = Owner
-    AnchorSideRight.Side = asrBottom
-    AnchorSideBottom.Control = CloseBtn
-    Left = 0
-    Height = 8
-    Top = 323
-    Width = 391
-    Anchors = [akLeft, akRight, akBottom]
-    Shape = bsBottomLine
+  inherited ParamsSplitter: TSplitter
+    Height = 345
   end
 end
diff --git a/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.pas b/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.pas
index a21605fa7..43e1aeaf1 100644
--- a/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.pas
+++ b/applications/lazstats/source/forms/analysis/nonparametric/signtestunit.pas
@@ -5,19 +5,14 @@ unit SignTestUnit;
 interface
 
 uses
-  Classes, SysUtils, FileUtil, LResources, Forms, Controls, Graphics, Dialogs,
-  StdCtrls, Buttons, ExtCtrls,
-  MainUnit, OutputUnit, FunctionsLib, Globals, DataProcs;
+  Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls, Buttons, ExtCtrls,
+  MainUnit, FunctionsLib, Globals, BasicStatsReportFormUnit;
 
 type
 
   { TSignTestFrm }
 
-  TSignTestFrm = class(TForm)
-    Bevel1: TBevel;
-    ResetBtn: TButton;
-    ComputeBtn: TButton;
-    CloseBtn: TButton;
+  TSignTestFrm = class(TBasicStatsReportForm)
     Var1In: TBitBtn;
     Var1Out: TBitBtn;
     Var2In: TBitBtn;
@@ -28,22 +23,22 @@ type
     Label2: TLabel;
     Label3: TLabel;
     VarList: TListBox;
-    procedure ComputeBtnClick(Sender: TObject);
-    procedure FormActivate(Sender: TObject);
-    procedure FormCreate(Sender: TObject);
-    procedure FormShow(Sender: TObject);
-    procedure ResetBtnClick(Sender: TObject);
     procedure Var1InClick(Sender: TObject);
     procedure Var1OutClick(Sender: TObject);
     procedure Var2InClick(Sender: TObject);
     procedure Var2OutClick(Sender: TObject);
+    procedure VarListDblClick(Sender: TObject);
     procedure VarListSelectionChange(Sender: TObject; User: boolean);
   private
-    { private declarations }
-    FAutoSized: Boolean;
-    procedure UpdateBtnStates;
+	
+  protected
+    procedure AdjustConstraints; override;
+    procedure Compute; override;
+    procedure UpdateBtnStates; override;
+    function Validate(out AMsg: String; out AControl: TWinControl): boolean; override;
+		
   public
-    { public declarations }
+    procedure Reset; override;
   end; 
 
 var
@@ -51,200 +46,105 @@ var
 
 implementation
 
+{$R *.lfm}
+
 uses
-  Math;
+  Math,
+  GridProcs;
+
 
 { TSignTestFrm }
 
-procedure TSignTestFrm.ResetBtnClick(Sender: TObject);
-var
-  i: integer;
+procedure TSignTestFrm.AdjustConstraints;
 begin
-  Var1Edit.Text := '';
-  Var2Edit.Text := '';
-  VarList.Items.Clear;
-  for i := 1 to NoVariables do
-    VarList.Items.Add(OS3MainFrm.DataGrid.Cells[i,0]);
-  UpdateBtnStates;
+  inherited;
+
+  ParamsPanel.Constraints.MinWidth := 4*CloseBtn.Width + 3*CloseBtn.BorderSpacing.Left;
+  ParamsPanel.Constraints.MinHeight := Var2Out.Top + Var2Out.Height +
+    ButtonBevel.Height + CloseBtn.Height + CloseBtn.Borderspacing.Top;
 end;
 
-procedure TSignTestFrm.Var1InClick(Sender: TObject);
+
+procedure TSignTestFrm.Compute;
 var
-  index: integer;
+  ColNoSelected: IntDyneVec = nil;
+  DifSigns: IntDyneVec = nil;
+  i, col1, col2, X, N, A, b, Temp: integer;
+  p, Q, Probability, z, NoDiff, CorrectedA, x1, x2: double;
+  SumProb: double;
+  lReport: TStrings;
 begin
-  index := VarList.ItemIndex;
-  if (index > -1) and (Var1Edit.Text = '') then
+  SumProb := 0.0;
+  SetLength(DifSigns, NoCases);
+
+  // Get column numbers and labels of variables selected
+  SetLength(ColNoSelected, 2);
+  ColNoSelected[0] := GetVariableIndex(OS3MainFrm.DataGrid, Var1Edit.Text);
+  ColNoSelected[1] := GetVariableIndex(OS3MainFrm.DataGrid, Var2Edit.Text);
+
+  p := 0.5;
+  Q := 0.5;
+
+  // Get sign of difference between pairs '(-1 := - ; 0 := no difference; +1 := +
+  A := 0;
+  b := 0;
+  NoDiff := 0.0;
+  for i := 1 to NoCases do
   begin
-    Var1Edit.Text := VarList.Items[index];
-    VarList.Items.Delete(index);
-  end;
-  UpdateBtnStates;
-end;
-
-procedure TSignTestFrm.Var1OutClick(Sender: TObject);
-begin
-  if Var1Edit.Text <> '' then
-  begin
-    VarList.Items.Add(Var1Edit.Text);
-    Var1Edit.Text := '';
-  end;
-  UpdateBtnStates;
-end;
-
-procedure TSignTestFrm.Var2InClick(Sender: TObject);
-var
-  index: integer;
-begin
-  index := VarList.ItemIndex;
-  if (index > -1) and (Var2Edit.Text = '') then
-  begin
-    Var2Edit.Text := VarList.Items[index];
-    VarList.Items.Delete(index);
-  end;
-  UpdateBtnStates;
-end;
-
-procedure TSignTestFrm.Var2OutClick(Sender: TObject);
-begin
-  if Var2Edit.Text <> '' then
-  begin
-    VarList.Items.Add(Var2Edit.Text);
-    Var2Edit.Text := '';
-  end;
-  UpdateBtnStates;
-end;
-
-procedure TSignTestFrm.VarListSelectionChange(Sender: TObject; User: boolean);
-begin
-  UpdateBtnStates;
-end;
-
-procedure TSignTestFrm.FormActivate(Sender: TObject);
-var
-  w: Integer;
-begin
-  if FAutoSized then
-    exit;
-
-  w := MaxValue([ResetBtn.Width, ComputeBtn.Width, CloseBtn.Width]);
-  ResetBtn.Constraints.MinWidth := w;
-  ComputeBtn.Constraints.MinWidth := w;
-  CloseBtn.Constraints.MinWidth := w;
-
-  Constraints.MinWidth := 4*w; //Width;
-  Constraints.MinHeight := Height;
-
-  FAutoSized := true;
-end;
-
-procedure TSignTestFrm.FormCreate(Sender: TObject);
-begin
-  Assert(OS3MainFrm <> nil);
-end;
-
-procedure TSignTestFrm.FormShow(Sender: TObject);
-begin
-  ResetBtnClick(self);
-end;
-
-procedure TSignTestFrm.ComputeBtnClick(Sender: TObject);
-var
-   i, k, col1, col2, X, N, A, b, Temp : integer;
-   ColNoSelected : IntDyneVec;
-   DifSigns : IntDyneVec;
-   p, Q, Probability, z, NoDiff, CorrectedA, x1, x2 : double;
-   SumProb : double;
-   cellstring: string;
-   lReport: TStrings;
-begin
-     if Var1Edit.Text = '' then
-     begin
-       MessageDlg('Variable 1 not selected.', mtError, [mbOK], 0);
-       exit;
-     end;
-
-     if Var2Edit.Text = '' then
-     begin
-       MessageDlg('Variable 2 not selected.', mtError, [mbOK], 0);
-       exit;
-     end;
-
-     SumProb := 0.0;
-     SetLength(DifSigns,NoCases);
-     SetLength(ColNoSelected,NoVariables);
-     k := 2;
-
-    // Get column numbers and labels of variables selected
-    for i := 1 to NoVariables do
+    if (not GoodRecord(OS3MainFrm.DataGrid, i, ColNoSelected)) then continue;
+    col1 := ColNoSelected[0];
+    col2 := ColNoSelected[1];
+    x1 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[col1, i]));
+    x2 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[col2, i]));
+    if (x1 > x2) then
     begin
-        cellstring := OS3MainFrm.DataGrid.Cells[i,0];
-        if cellstring = Var1Edit.Text then ColNoSelected[0] := i;
-        if cellstring = Var2Edit.Text then ColNoSelected[1] := i;
+      DifSigns[i-1] := 1;
+      A := A + 1;
+    end;
+    if (x1 < x2) then
+    begin
+      DifSigns[i-1] := -1;
+      b  := b + 1;
+    end;
+    if (x1 = x2) then
+    begin
+      DifSigns[i-1] := 0;
+      NoDiff := NoDiff + 1.0;
+    end;
+  end;
+
+  // Show results
+  lReport := TStringList.Create;
+  try
+    lReport.Add('RESULTS FOR THE SIGN TEST');
+    lReport.Add('');
+    lReport.Add('Frequency of %d out of %d observed + sign differences.', [A, NoCases]);
+    lReport.Add('Frequency of %d out of %d observed - sign differences.', [b, NoCases]);
+    lReport.Add('Frequency of %.0f out of %d observed no differences.', [NoDiff, NoCases]);
+    lReport.Add('');
+    lReport.Add('The theoretical proportion expected for +''s or -''s is 0.5 ');
+    lReport.Add('The test is for the probability of the +''s or -''s (which ever is fewer)');;
+    lReport.Add('as small or smaller than that observed given the expected proportion.');
+    lReport.Add('');
+
+    // Swap A and B around if A > B
+    if (A > b) then
+    begin
+      Temp := A;
+      A := b;
+      b := Temp;
     end;
 
-    p := 0.5;
-    Q := 0.5;
-
-    // Get sign of difference between pairs '(-1 := - ; 0 := no difference; +1 := +
-    A := 0;
-    b := 0;
-    NoDiff := 0.0;
-    for i := 1 to NoCases do
+    N := A + b;
+    if (N > 25) then // Use normal distribution approximation
     begin
-        if (not GoodRecord(i,k,ColNoSelected)) then continue;
-        col1 := ColNoSelected[0];
-        col2 := ColNoSelected[1];
-        x1 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[col1,i]));
-        x2 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[col2,i]));
-        if (x1 > x2) then
-        begin
-            DifSigns[i-1] := 1;
-            A := A + 1;
-        end;
-        if (x1 < x2) then
-        begin
-            DifSigns[i-1] := -1;
-            b  := b + 1;
-        end;
-        if (x1 = x2) then
-        begin
-            DifSigns[i-1] := 0;
-            NoDiff := NoDiff + 1.0;
-        end;
-    end;
-
-    // Show results
-    lReport := TStringList.Create;
-    try
-      lReport.Add('RESULTS FOR THE SIGN TEST');
-      lReport.Add('');
-      lReport.Add('Frequency of %d out of %d observed + sign differences.', [A, NoCases]);
-      lReport.Add('Frequency of %d out of %d observed - sign differences.', [b, NoCases]);
-      lReport.Add('Frequency of %.0f out of %d observed no differences.', [NoDiff, NoCases]);
-      lReport.Add('');
-      lReport.Add('The theoretical proportion expected for +''s or -''s is 0.5 ');
-      lReport.Add('The test is for the probability of the +''s or -''s (which ever is fewer)');;
-      lReport.Add('as small or smaller than that observed given the expected proportion.');
-      lReport.Add('');
-
-      // Swap A and B around if A > B
-      if (A > b) then
-      begin
-        Temp := A;
-        A := b;
-        b := Temp;
-      end;
-
-      N := A + b;
-      if (N > 25) then // Use normal distribution approximation
-      begin
-        CorrectedA := A;
-        if (A < N * p) then  CorrectedA := A + 0.5;
-        if (A > N * p) then CorrectedA := A - 0.5;
-        z := (CorrectedA - N * p) / sqrt(N * p * Q);
-        lReport.Add('Z value for Normal Distribution approximation: %.3f', [z]);
-        Probability := probz(z);
-        lReport.Add('Probability: %.4f', [Probability]);
+      CorrectedA := A;
+      if (A < N * p) then  CorrectedA := A + 0.5;
+      if (A > N * p) then CorrectedA := A - 0.5;
+      z := (CorrectedA - N * p) / sqrt(N * p * Q);
+      lReport.Add('Z value for Normal Distribution approximation: %.3f', [z]);
+      Probability := ProbZ(z);
+      lReport.Add('Probability: %.4f', [Probability]);
     end
     else // Use binomial fomula
     begin
@@ -259,14 +159,126 @@ begin
       lReport.Add('Binomial Probability of %d or smaller out of %d: %.4f', [A, N, SumProb]);
     end;
 
-    DisplayReport(lReport);
+    FReportFrame.DisplayReport(lReport);
+
   finally
     lReport.Free;
-    DifSigns := nil;
-    ColNoSelected := nil;
   end;
 end;
 
+
+procedure TSignTestFrm.Reset;
+var
+  i: integer;
+begin
+  inherited;
+  Var1Edit.Clear;
+  Var2Edit.Clear;
+  VarList.Items.Clear;
+  for i := 1 to NoVariables do
+    VarList.Items.Add(OS3MainFrm.DataGrid.Cells[i,0]);
+  UpdateBtnStates;
+end;
+
+
+function TSignTestFrm.Validate(out AMsg: String; out AControl: TWinControl): boolean;
+begin
+  Result := false;
+	
+  if Var1Edit.Text = '' then
+  begin
+    AMsg := 'Variable 1 not selected.';
+    AControl := Var1Edit;
+    exit;
+  end;
+
+  if Var2Edit.Text = '' then
+  begin
+    AMsg := 'Variable 2 not selected.';
+    AControl := Var2Edit;
+    exit;
+  end;
+
+  Result := true;
+end;
+
+	
+procedure TSignTestFrm.Var1InClick(Sender: TObject);
+var
+  index: integer;
+begin
+  index := VarList.ItemIndex;
+  if (index > -1) and (Var1Edit.Text = '') then
+  begin
+    Var1Edit.Text := VarList.Items[index];
+    VarList.Items.Delete(index);
+  end;
+  UpdateBtnStates;
+end;
+
+
+procedure TSignTestFrm.Var1OutClick(Sender: TObject);
+begin
+  if Var1Edit.Text <> '' then
+  begin
+    VarList.Items.Add(Var1Edit.Text);
+    Var1Edit.Text := '';
+  end;
+  UpdateBtnStates;
+end;
+
+
+procedure TSignTestFrm.Var2InClick(Sender: TObject);
+var
+  index: integer;
+begin
+  index := VarList.ItemIndex;
+  if (index > -1) and (Var2Edit.Text = '') then
+  begin
+    Var2Edit.Text := VarList.Items[index];
+    VarList.Items.Delete(index);
+  end;
+  UpdateBtnStates;
+end;
+
+
+procedure TSignTestFrm.Var2OutClick(Sender: TObject);
+begin
+  if Var2Edit.Text <> '' then
+  begin
+    VarList.Items.Add(Var2Edit.Text);
+    Var2Edit.Text := '';
+  end;
+  UpdateBtnStates;
+end;
+
+
+procedure TSignTestFrm.VarListDblClick(Sender: TObject);
+var
+  index: Integer;
+  s: String;
+begin
+  index := Varlist.ItemIndex;;
+  if index > -1 then
+  begin
+    s := VarList.Items[index];
+    if Var1Edit.Text = '' then
+      Var1Edit.Text := s
+    else
+    if Var2Edit.Text = '' then
+      Var2Edit.Text := s;
+    Varlist.Items.Delete(index);
+    UpdateBtnStates;
+  end;
+end;
+
+
+procedure TSignTestFrm.VarListSelectionChange(Sender: TObject; User: boolean);
+begin
+  UpdateBtnStates;
+end;
+
+
 procedure TSignTestFrm.UpdateBtnStates;
 begin
   Var1In.Enabled := (VarList.ItemIndex > -1) and (Var1Edit.Text = '');
@@ -276,8 +288,5 @@ begin
 end;
 
 
-initialization
-  {$I signtestunit.lrs}
-
 end.