unit TwoPropUnit;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, Forms, Controls,
  Graphics, Dialogs, ExtCtrls, StdCtrls, ComCtrls, Buttons, MainUnit, Globals,
  FunctionsLib, BasicStatsReportFormUnit;

type

  { TTwoPropForm }

  TTwoPropForm = class(TBasicStatsReportForm)
    Bevel2: TBevel;
    Bevel3: TBevel;
    Bevel5: TBevel;
    LabelCorner: TLabel;
    Notebook: TNotebook;
    Page1: TPage;
    Page2: TPage;
    Page3: TPage;
    Panel3: TPanel;
    Panel4: TPanel;
    DepFreq00: TEdit;
    DepFreq10: TEdit;
    DepFreq01: TEdit;
    DepFreq11: TEdit;
    CIntervalEdit: TEdit;
    GrpEdit: TEdit;
    GrpLabel: TLabel;
    ConfLabel: TLabel;
    Var1In: TBitBtn;
    Var2In: TBitBtn;
    Var1Out: TBitBtn;
    GrpIn: TBitBtn;
    Var2Out: TBitBtn;
    Var2Edit: TEdit;
    Var2Label: TLabel;
    Var1Edit: TEdit;
    IndSize2: TEdit;
    IndSize1: TEdit;
    IndFreq2: TEdit;
    IndFreq1: TEdit;
    Samp1Label: TLabel;
    Samp21Label: TLabel;
    Label11: TLabel;
    Var1Label: TLabel;
    Samp2Label: TLabel;
    Samp1SizeLabel: TLabel;
    Samp2SizeLabel: TLabel;
    DepSamp2Label: TLabel;
    DepSamp1Label: TLabel;
    Samp10Label: TLabel;
    Samp11Label: TLabel;
    Samp20Label: TLabel;
    GrpOut: TBitBtn;
    VarList: TListBox;
    DataSourceGroup: TRadioGroup;
    DepIndepGroup: TRadioGroup;
    procedure GrpInClick(Sender: TObject);
    procedure GrpOutClick(Sender: TObject);
    procedure DataSourceGroupClick(Sender: TObject);
    procedure DepIndepGroupClick(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; {%H-}User: boolean);

  private
    independent: boolean;
    griddata: boolean;
		
  protected
    procedure AdjustConstraints; override;
    procedure Compute; override;
    procedure UpdateBtnStates; override;
    function Validate(out AMsg: String; out AControl: TWinControl): Boolean; override;

  public
    constructor Create(AOwner: TComponent); override;
    procedure Reset; override;
  end; 

var
  TwoPropForm: TTwoPropForm;

implementation

{$R *.lfm}

uses
  Math,
  GridProcs;


{ TTwoPropForm }

constructor TTwoPropForm.Create(AOwner: TComponent);
begin
  inherited;
  CIntervalEdit.Text := FormatFloat('0.0', DEFAULT_CONFIDENCE_LEVEL_PERCENT);
end;


procedure TTwoPropForm.AdjustConstraints;
var
  w: Integer;
begin
  inherited;

  w := Max(DataSourceGroup.Width, DepIndepGroup.Width);
  DataSourceGroup.Constraints.MinWidth := w;
  DepIndepGroup.Constraints.MinWidth := w;
  ParamsPanel.Constraints.MinWidth := Max(
    4*CloseBtn.Width + 3*CloseBtn.BorderSpacing.Left,
    2*w + Bevel5.Width
  );
  ParamsPanel.Constraints.MinHeight := DataSourceGroup.Height +
    Notebook.BorderSpacing.Top + Var2Out.Top + Var2Out.Height +
    Notebook.BorderSpacing.Bottom + CIntervalEdit.Height + ButtonBevel.Height +
    CloseBtn.BorderSpacing.Top + CloseBtn.Height;
end;


procedure TTwoPropForm.Compute;
var
  ConfInt, Prop1, Prop2, zstatistic, zprobability: double;
  PropDif, stderr, UCL, LCL, value1, value2, ztest: double;
  P, Q: double;
  i: Integer; //, v1, v2, NoSelected,
  f1, f2, f3, f4, ncases1, ncases2: integer;
  min, max, group, AB, AC, CD, BD: integer;
  ColNoSelected: IntDyneVec = nil;
  lReport: TStrings;
begin
  // Initialize output form
  stderr := 0.0;
  PropDif := 0.0;
//  v2 := 0;
  ztest := 0.0;
  Prop1 := 0.0;
  Prop2 := 0.0;
//  NoSelected := 0;
//  v1 := 0;
  zstatistic := 0.0;
  zprobability := 0.0;
  UCL := 0.0;
  LCL := 0.0;

  SetLength(ColNoSelected,NoVariables);

  ConfInt := (100.0 - StrToFloat(CIntervalEdit.Text)) / 2.0 ;
  ConfInt := (100.0 - ConfInt) / 100.0; // one tail

  ncases1 := 0;
  ncases2 := 0;
  f1 := 0;
  f2 := 0;
  f3 := 0;
  f4 := 0;
  if independent then
    Var2Edit.Text := GrpEdit.Text;

  if griddata then // data read from grid
  begin
    SetLength(ColNoSelected, 2);
    ColNoSelected[0] := GetVariableIndex(OS3MainFrm.DataGrid, Var1Edit.Text);
    ColNoSelected[1] := GetVariableIndex(OS3MainFrm.DataGrid, Var2Edit.Text);
     {
    for i := 1 to NoVariables do
    begin
      if Var1Edit.Text = OS3MainFrm.DataGrid.Cells[i,0] then
      begin
        v1 := i;
        ColNoSelected[0] := i;
      end;

      if Var2Edit.Text = OS3MainFrm.DataGrid.Cells[i,0] then
      begin
        v2 := i;
        ColNoSelected[1] := i;
      end;
    end; // next variable
     }

    f1 := 0;
    f2 := 0;
    nCases1 := 0;
    if not independent then // correlated data
    begin
      for i := 1 to NoCases do
      begin
        if not GoodRecord(OS3MainFrm.DataGrid, i, ColNoSelected) then continue;
        nCases1 := nCases1 + 1;
        value1 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[ColNoSelected[0], i]));
        value2 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[ColNoSelected[1], i]));
        f1 := f1 + round(value1);
        f2 := f2 + round(value2);
      end; // next case
      f3 := nCases1 - f1;
      f4 := nCases1 - f2;
      AB := f1 + f2;
      AC := f1 + f3;
      CD := f3 + f4;
      BD := f2 + f4;
      Prop1 := BD / nCases1;
      Prop2 := AB / nCases1;
      stderr := sqrt((f1 / nCases1 + f4 / nCases1) / nCases1);
      PropDif := Prop1 - Prop2;
      zstatistic := PropDif / stderr;
      ztest := InverseZ(ConfInt);
      zprobability := 1.0 - ProbZ(abs(zstatistic));
      UCL := PropDif + stderr * ztest;
      LCL := PropDif - stderr * ztest;
    end; // if not independent

    if independent then
    begin
      min := MaxInt;
      max := min;
      for i := 1 to NoCases do
      begin
        if not GoodRecord(OS3MainFrm.DataGrid, i, ColNoSelected) then continue;
        group := round(StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[ColNoSelected[1], i])));
        if group < min then min := group;
        if group > max then max := group;
      end;

      for i := 1 to NoCases do
      begin
        if not GoodRecord(OS3MainFrm.DataGrid, i, ColNoSelected) then continue;
        value1 := StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[ColNoSelected[0], i]));
        group := round(StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[ColNoSelected[1], i])));
        if group = min then
        begin
          f1 := f1 + round(value1);
          ncases1 := ncases1 + 1;
        end else
        begin
          f2 := f2 + round(value1);
          ncases2 := ncases2 + 1;
        end;
      end; // next case

      Prop1 := f1 / ncases1;
      Prop2 := f2 / ncases2;
      PropDif := Prop1 - Prop2;
      P := (f1 + f2) / (ncases1 + ncases2);
      Q := 1.0 - P;
      stderr := sqrt(P * Q * ((1.0 / ncases1) + (1.0 / ncases2)));
      zstatistic := (Prop1 - Prop2) / stderr;
      zprobability := 1.0 - probz(abs(zstatistic));
      ztest := inversez(ConfInt);
      UCL := PropDif + ztest * stderr;
      LCL := PropDif - ztest * stderr;
    end; // end if independent
  end; // if reading grid data

  if not griddata then // data read from form
  begin
    if not independent then // correlated data
    begin
      f1 := round(StrToFloat(DepFreq00.Text));
      f2 := round(StrToFloat(DepFreq10.Text));
      f3 := round(StrToFloat(DepFreq01.Text));
      f4 := round(StrToFloat(DepFreq11.Text));
      ncases1 := f1 + f2 + f3 + f4;
      AB := f1 + f2;
      AC := f1 + f3;
      CD := f3 + f4;
      BD := f2 + f4;
      Prop1 := BD / ncases1;
      Prop2 := AB / ncases1;
      stderr := sqrt((f1 / ncases1 + f4 / ncases1) / ncases1);
      PropDif := Prop1 - Prop2;
      zstatistic := PropDif / stderr;
      ztest := inversez(ConfInt);
      zprobability := 1.0 - probz(abs(zstatistic));
      UCL := PropDif + stderr * ztest;
      LCL := PropDif - stderr * ztest;
    end; // if not independent

    if independent then // independent data
    begin
      f1 := StrToInt(IndFreq1.Text);
      f2 := StrToInt(IndFreq2.Text);
      ncases1 := StrToInt(IndSize1.Text);
      ncases2 := StrToInt(IndSize2.Text);
      Prop1 := f1 / ncases1;
      Prop2 := f2 / ncases2;
      PropDif := Prop1 - Prop2;
      P := (f1 + f2) / (ncases1 + ncases2);
      Q := 1.0 - P;
      stderr := sqrt(P * Q * ((1.0 / ncases1) + (1.0 / ncases2)));
      zstatistic := (Prop1 - Prop2) / stderr;
      zprobability := 1.0 - probz(abs(zstatistic));
      ztest := inversez(ConfInt);
      UCL := PropDif + ztest * stderr;
      LCL := PropDif - ztest * stderr;
    end;
  end;

  // Print the results
  lReport := TStringList.Create;
  try
    lReport.Add('COMPARISON OF TWO PROPORTIONS');
    lReport.Add('');
    if not independent then
    begin
      lReport.Add('Test for Difference Between Two Dependent Proportions');
      lReport.Add('');
      lReport.Add('Entered Values');
      lReport.Add('');
      lReport.Add('Sample               1');
      lReport.Add('                 0      1    sum');
      lReport.Add('           -----------------------');
      lReport.Add('       0  |%5d   %5d   %5d |', [f1, f2, AB]);
      lReport.Add('  2        --------|-------|------');
      lReport.Add('       1  |%5d   %5d   %5d |', [f3, f4, CD]);
      lReport.Add('           --------|-------|------');
      lReport.Add(' sum      | %5d  %5d   %5d |', [AC, BD, ncases1]);
      lReport.Add('');
      lReport.Add('Confidence Level selected:       %9s',  [CIntervalEdit.Text]);
      lReport.Add('Proportion 1:                    %9.3f', [Prop1]);
      lReport.Add('Proportion 2:                    %9.3f', [Prop2]);
      lReport.Add('Number of cases:                 %9d',   [nCases1]);
      lReport.Add('Difference in proportions:       %9.3f', [PropDif]);
      lReport.Add('Standard Error of Difference:    %9.3f', [stderr]);
      lReport.Add('z test statistic:                %9.3f', [zStatistic]);
      lReport.Add('  with probability               %9.4f', [zProbability]);
      lReport.Add('z value for confidence interval: %9.3f', [zTest]);
      lReport.Add('Confidence Interval:             %9.3f ... %.3f', [LCL, UCL]);
    end;

    if independent then
    begin
      lReport.Add('Test for Difference Between Two Independent Proportions');
      lReport.Add('');
      lReport.Add('Entered Values');
      lReport.Add('');
      lReport.Add('Sample 1: Frequency %5d for %5d cases.', [f1, ncases1]);
      lReport.Add('Sample 2: Frequency %5d for %5d cases.', [f2, ncases2]);
      lReport.Add('');
      lReport.Add('Proportion 1:                    %9.3f', [Prop1]);
      lReport.Add('Proportion 2:                    %9.3f', [Prop2]);
      lReport.Add('Difference:                      %9.3f', [PropDif]);
      lReport.Add('Standard Error of Difference:    %9.3f', [stderr]);
      lReport.Add('Confidence Level selected:       %9s',  [CIntervalEdit.Text]);
      lReport.Add('z test statistic:                %9.3f', [zStatistic]);
      lReport.Add('  with probability               %9.4f', [zProbability]);
      lReport.Add('z value for confidence interval: %9.3f', [ztest]);
      lReport.Add('Confidence Interval:             %9.3f ... %.3f', [LCL, UCL]);
    end;

    FReportFrame.DisplayReport(lReport);

  finally
    lReport.Free;
  end;
end;


procedure TTwoPropForm.GrpInClick(Sender: TObject);
var
  index: Integer;
begin
  index := VarList.ItemIndex;
  if (index > -1) and (GrpEdit.Text = '') then
  begin
    GrpEdit.Text := VarList.Items[index];
    VarList.Items.Delete(index);
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.GrpOutClick(Sender: TObject);
begin
  if GrpEdit.Text <> '' then
  begin
    VarList.Items.Add(GrpEdit.Text);
    GrpEdit.Text := '';
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.DataSourceGroupClick(Sender: TObject);
begin
  griddata := (DataSourceGroup.ItemIndex = 1);
  DepIndepGroupClick(nil);
end;


procedure TTwoPropForm.DepIndepGroupClick(Sender: TObject);
begin
  case DepIndepGroup.ItemIndex of
     0: begin
          independent := true;
          if griddata then
            Notebook.PageIndex := 0
          else
            Notebook.PageIndex := 1;
        end;
     1: begin
          independent := false;
          if griddata then
            Notebook.PageIndex := 0
          else
            Notebook.PageIndex := 2;
        end;
  end;

  Var2Edit.Visible := independent;
  Var2Label.Visible := independent;
  Var2In.Visible := independent;
  Var2Out.Visible := independent;

  GrpEdit.Visible := not independent;
  GrpLabel.Visible := not independent;
  GrpIn.Visible := not independent;
  GrpOut.Visible := not independent;

end;


procedure TTwoPropForm.Reset;
var
  i: integer;
begin
  inherited;

  DataSourceGroup.ItemIndex := 0;
  DepIndepGroup.ItemIndex := 0;

  VarList.Clear;
  for i := 1 to NoVariables do
    VarList.Items.Add(OS3MainFrm.DataGrid.Cells[i,0]);

  Var1Edit.Clear;
  Var2Edit.Clear;
  independent := true;
  griddata := false;
  GrpLabel.Visible := true;
  GrpEdit.Visible := true;
  GrpIn.Visible := true;
  GrpOut.Visible := true;
  GrpEdit.Clear;
  Var2Edit.Visible := false;
  Var2Label.Visible := false;
  Var2In.Visible := false;
  Var2Out.Visible := false;
  DepFreq00.Clear;
  DepFreq01.Clear;
  DepFreq10.Clear;
  DepFreq11.Clear;
  IndFreq1.Clear;
  IndFreq2.Clear;
  IndSize1.Clear;
  IndSize2.Clear;

  Notebook.PageIndex := 1;

  UpdateBtnStates;
end;


procedure TTwoPropForm.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);
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.Var1OutClick(Sender: TObject);
begin
  if Var1Edit.Text <> '' then
  begin
    VarList.Items.Add(Var1Edit.Text);
    Var1Edit.Text := '';
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.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);
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.Var2OutClick(Sender: TObject);
begin
  if Var2Edit.Text <> '' then
  begin
    VarList.Items.Add(Var2Edit.Text);
    Var2Edit.Text := '';
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.UpdateBtnStates;
begin
  inherited;
  Var1In.Enabled := (VarList.ItemIndex > -1) and (Var1Edit.Text = '');
  Var2In.Enabled := (VarList.ItemIndex > -1) and (Var2Edit.Text = '');
  GrpIn.Enabled := (VarList.ItemIndex > -1) and (GrpEdit.Text = '');

  Var1Out.Enabled := Var1Edit.Text <> '';
  Var2Out.Enabled := Var2Edit.Text <> '';
  GrpOut.Enabled := GrpEdit.Text <> '';
end;


function TTwoPropForm.Validate(out AMsg: String; out AControl: TWinControl): Boolean;
var
  n: Integer;
begin
  Result := false;
  AControl := nil;
  AMsg := '';
  if Notebook.PageIndex = 0 then
  begin
    if Var1Edit.Text = '' then
    begin
      AControl := Var1Edit;
      AMsg := 'First variable not specified.';
      exit;
    end;
    case DepIndepGroup.ItemIndex of
      0: if (GrpEdit.Text = '') then
         begin
           AControl := GrpEdit;
           AMsg := 'Group code not specified';
           exit;
         end;
      1: if (Var2Edit.Text = '') then begin
           AControl := Var2Edit;
           AMsg := 'Second variable not specified.';
           exit;
         end;
    end;
  end else
  if Notebook.PageIndex = 1 then
  begin
    if (IndFreq1.Text = '') or not TryStrToInt(IndFreq1.Text, n) or (n < 0) then
    begin
      AControl := IndFreq1;
      AMsg := 'Invalid input for Sample 1 frequency';
      exit;
    end;
    if (IndFreq2.Text = '') or not TryStrToInt(IndFreq2.Text, n) or (n < 0) then
    begin
      AControl := IndFreq2;
      AMsg := 'Invalid input for Sample 2 frequency';
      exit;
    end;
    if (IndSize1.Text = '') or not TryStrToInt(IndSize1.Text, n) or (n <= 0) then
    begin
      AControl := IndSize1;
      AMsg := 'Invald input for size of sample 1';
      exit;
    end;
    if (IndSize2.Text = '') or not TryStrToInt(IndSize2.Text, n) or (n <= 0) then
    begin
      AControl := IndSize2;
      AMsg := 'Invalud input for size of sample 2';
      exit;
    end;
  end else
  if Notebook.PageIndex = 2 then
  begin
    if (DepFreq00.Text = '') or not TryStrToInt(DepFreq00.Text, n) or (n < 0) then
      AControl := DepFreq00
    else
    if (DepFreq01.Text = '') or not TryStrToInt(DepFreq01.Text, n) or (n < 0) then
      AControl := DepFreq01
    else
    if (DepFreq10.Text = '') or not TryStrToInt(DepFreq10.Text, n) or (n < 0) then
      AControl := DepFreq10
    else
    if (DepFreq11.Text = '') or not TryStrToInt(DepFreq11.Text, n) or (n < 0) then
      AControl := DepFreq11;
    if AControl <> nil then
    begin
      AMsg := 'Invalid input.';
      exit;
    end;
  end;
  Result := true;
end;


procedure TTwoPropForm.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
    begin
      Var1Edit.Text := s;
      VarList.Items.Delete(index);
    end else
    if independent and (GrpEdit.Text = '') then
    begin
      GrpEdit.Text := s;
      VarList.Items.Delete(index);
    end else
    if (not independent) and (Var2Edit.Text = '') then
    begin
      Var2Edit.Text := s;
      VarList.Items.Delete(index);
    end;
    UpdateBtnStates;
  end;
end;


procedure TTwoPropForm.VarListSelectionChange(Sender: TObject; User: boolean);
begin
  UpdateBtnStates;
end;


end.