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lazarus-ccr/applications/lazstats/source/forms/analysis/measurement_programs/raschunit.pas

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unit RaschUnit;
{$mode objfpc}{$H+}
interface
uses
Classes, SysUtils, FileUtil, LResources, Forms, Controls, Graphics, Dialogs,
StdCtrls, Buttons, ExtCtrls,
MainUnit, OutputUnit, FunctionsLib, GraphLib, Globals,
DataProcs, ContextHelpUnit;
type
{ TRaschFrm }
TRaschFrm = class(TForm)
Bevel1: TBevel;
HelpBtn: TButton;
ResetBtn: TButton;
CancelBtn: TButton;
ComputeBtn: TButton;
ReturnBtn: TButton;
ProxChk: TCheckBox;
PlotItemsChk: TCheckBox;
PlotScrsChk: TCheckBox;
ItemInfoChk: TCheckBox;
TestInfoChk: TCheckBox;
GroupBox1: TGroupBox;
InBtn: TBitBtn;
Label2: TLabel;
ItemList: TListBox;
OutBtn: TBitBtn;
Label1: TLabel;
VarList: TListBox;
procedure ComputeBtnClick(Sender: TObject);
procedure FormActivate(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure FormShow(Sender: TObject);
procedure HelpBtnClick(Sender: TObject);
procedure InBtnClick(Sender: TObject);
procedure OutBtnClick(Sender: TObject);
procedure ResetBtnClick(Sender: TObject);
private
{ private declarations }
FAutoSized: Boolean;
procedure ANALYZE(VAR itemfail : IntDyneVec;
VAR grpfail : IntDyneVec;
VAR f : IntDyneMat;
VAR T : integer;
VAR grppass : IntDyneVec;
VAR itempass : IntDyneVec;
r, C1 : integer;
VAR min : double;
VAR max : double;
VAR p2 : DblDyneVec);
procedure EXPAND(v1, v2 : double;
VAR xexpand : double;
VAR yexpand : double);
procedure FinishIt(r : integer;
VAR i5 : IntDyneVec;
VAR rptbis : DblDyneVec;
VAR rbis : DblDyneVec;
VAR slope : DblDyneVec;
VAR mean : DblDyneVec;
VAR itemfail : IntDyneVec;
VAR P : DblDyneVec );
procedure FREQUENCIES(C1, r : integer;
VAR f : IntDyneMat;
VAR rowtot : IntDyneVec;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec;
T : integer;
VAR S : IntDyneVec);
procedure GETLOGS(VAR L : DblDyneVec;
VAR L1 : DblDyneVec;
VAR L2 : DblDyneVec;
VAR g : DblDyneVec;
VAR g2 : DblDyneVec;
VAR f2 : DblDyneVec;
VAR rowtot : IntDyneVec;
k : integer;
VAR s5 : IntDyneVec;
VAR S : IntDyneVec;
T, r, C1 : integer;
VAR v1 : double;
VAR v2 : double);
procedure GETSCORES(VAR noselected : integer;
VAR selected : IntDyneVec;
NoCases : integer;
f : IntDyneMat;
VAR mean : DblDyneVec;
VAR xsqr : DblDyneVec;
VAR sumxy : DblDyneVec;
VAR S : IntDyneVec;
VAR X : IntDyneVec;
VAR sumx : double;
VAR sumx2 : double;
VAR N : integer);
procedure MAXABILITY(VAR expdcnt : DblDyneVec;
VAR d2 : DblDyneVec;
VAR e2 : DblDyneVec;
VAR p1 : DblDyneMat;
VAR p2 : DblDyneVec;
VAR P : DblDyneVec;
C1, r : integer;
D : DblDyneMat;
VAR s5 : IntDyneVec;
noloops : integer);
function MAXITEM(VAR R1 : DblDyneVec;
VAR d1 : DblDyneVec;
VAR p1 : DblDyneMat;
VAR D : DblDyneMat;
VAR e1 : DblDyneVec;
VAR p2 : DblDyneVec;
VAR P : DblDyneVec;
VAR S : IntDyneVec;
VAR rowtot : IntDyneVec;
T, r, C1 : integer) : double;
procedure MAXOUT(r, C1 : integer;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec;
VAR P : DblDyneVec;
VAR p2 : DblDyneVec);
procedure PROX(VAR P : DblDyneVec;
VAR p2 : DblDyneVec;
k, r, C1 : integer;
VAR L1 : DblDyneVec;
yexpand, xexpand : double;
VAR g : DblDyneVec;
T : integer;
VAR rowtot : IntDyneVec;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec);
Function REDUCE(k : integer;
VAR r : integer;
VAR T : integer;
VAR C1 : integer;
VAR i5 : IntDyneVec;
VAR rowtot : IntDyneVec;
VAR s5 : IntDyneVec;
VAR f : IntDyneMat;
VAR S : IntDyneVec) : integer;
procedure SLOPES(VAR rptbis : DblDyneVec;
VAR rbis : DblDyneVec;
VAR slope : DblDyneVec;
N : integer;
sumx, sumx2 : double;
VAR sumxy : DblDyneVec;
r : integer;
VAR xsqr : DblDyneVec;
VAR mean : DblDyneVec);
procedure TESTFIT(r, C1 : integer;
VAR f : IntDyneMat;
VAR S : IntDyneVec;
VAR P : DblDyneVec;
VAR p2 : DblDyneVec;
T : integer);
procedure PLOTINFO(k, r : integer;
VAR info : DblDyneMat;
VAR A : DblDyneMat;
VAR slope : DblDyneVec;
VAR P : DblDyneVec);
procedure plot(VAR xyarray : DblDyneMat;
arraysize : integer;
Title : string;
Vdivisions, Hdivisions : integer);
procedure PlotItems(r : integer; i5 : IntDyneVec; P : DblDyneVec);
procedure PlotScrs(C1 : integer; s5 : IntDyneVec; p2 : DblDyneVec);
procedure PlotTest(VAR TestInfo : DblDyneMat;
arraysize : integer;
Title : string;
Vdivisions, Hdivisions : integer);
public
{ public declarations }
end;
var
RaschFrm: TRaschFrm;
implementation
uses
Math;
{ TRaschFrm }
procedure TRaschFrm.ResetBtnClick(Sender: TObject);
VAR i : integer;
begin
VarList.Clear;
ItemList.Clear;
OutBtn.Enabled := false;
InBtn.Enabled := true;
ProxChk.Checked := false;
PlotItemsChk.Checked := false;
PlotScrsChk.Checked := false;
ItemInfoChk.Checked := false;
TestInfoChk.Checked := false;
for i := 1 to NoVariables do
VarList.Items.Add(OS3MainFrm.DataGrid.Cells[i,0]);
end;
procedure TRaschFrm.FormActivate(Sender: TObject);
var
w: Integer;
begin
if FAutoSized then
exit;
w := MaxValue([HelpBtn.Width, ResetBtn.Width, CancelBtn.Width, ComputeBtn.Width, ReturnBtn.Width]);
HelpBtn.Constraints.MinWidth := w;
ResetBtn.Constraints.MinWidth := w;
CancelBtn.Constraints.MinWidth := w;
ComputeBtn.Constraints.MinWidth := w;
ReturnBtn.Constraints.MinWidth := w;
Constraints.MinWidth := Width;
Constraints.MinHeight := Height;
FAutoSized := true;
end;
procedure TRaschFrm.FormCreate(Sender: TObject);
begin
Assert(OS3MainFrm <> nil);
if OutputFrm = nil then
Application.CreateForm(TOutputFrm, OutputFrm);
if GraphFrm = nil then
Application.CreateForm(TGraphFrm, GraphFrm);
end;
procedure TRaschFrm.FormShow(Sender: TObject);
begin
ResetBtnClick(self);
end;
procedure TRaschFrm.HelpBtnClick(Sender: TObject);
begin
if ContextHelpForm = nil then
Application.CreateForm(TContextHelpForm, ContextHelpForm);
ContextHelpForm.HelpMessage((Sender as TButton).tag);
end;
procedure TRaschFrm.ComputeBtnClick(Sender: TObject);
var
i, j, k1, N, C1, r, T,noloops : integer;
sumx, sumx2, v1, v2, xexpand, yexpand, d9, min, max : double;
X, rowtot, itemfail, itempass, grpfail, grppass, S, s5, i5 : IntDyneVec;
f : IntDyneMat;
mean, xsqr, sumxy, L, L1, L2, g, g2, f2, P, p2, R1, d1, e1 : DblDyneVec;
expdcnt, d2 : DblDyneVec;
e2, rptbis, rbis, slope : DblDyneVec;
p1, D, info, A : DblDyneMat;
NoSelected : integer;
ColNoSelected : IntDyneVec;
finished : boolean;
cellstring : string;
error : integer;
begin
SetLength(ColNoSelected,NoVariables);
SetLength(mean,NoVariables);
SetLength(xsqr,NoVariables);
SetLength(sumxy,NoVariables);
SetLength(L,NoVariables);
SetLength(L1,NoVariables);
SetLength(L2,NoVariables);
SetLength(g,NoVariables);
SetLength(g2,NoVariables);
SetLength(f2,NoVariables);
SetLength(P,NoVariables);
SetLength(p2,NoVariables);
SetLength(R1,NoVariables);
SetLength(d1,NoVariables);
SetLength(e1,NoVariables);
SetLength(expdcnt,NoVariables);
SetLength(d2,NoVariables);
SetLength(e2,NoVariables);
SetLength(rptbis,NoVariables);
SetLength(rbis,NoVariables);
SetLength(slope,NoVariables);
SetLength(p1,NoVariables,NoVariables);
SetLength(D,NoVariables,NoVariables);
SetLength(info,52,52);
SetLength(A,52,2);
SetLength(X,NoVariables);
SetLength(rowtot,NoVariables);
SetLength(itemfail,NoVariables);
SetLength(itempass,NoVariables);
SetLength(grpfail,NoVariables);
SetLength(grppass,NoVariables);
SetLength(S,NoVariables+2);
SetLength(s5,NoVariables);
SetLength(i5,NoVariables);
SetLength(f,NoVariables+2,NoVariables+2);
if (NoVariables < 1) then
begin
ShowMessage('ERROR! You must have data in your data grid!');
exit;
end;
// Get selected variables
NoSelected := ItemList.Items.Count;
for i := 1 to NoSelected do
begin
for j := 1 to NoVariables do
begin
cellstring := OS3MainFrm.DataGrid.Cells[j,0];
if cellstring = ItemList.Items.Strings[i-1] then
ColNoSelected[i-1] := j;
end;
end;
//begin ( main program )
finished := false;
N := NoCases;
k1 := NoSelected;
GETSCORES(NoSelected, ColNoSelected, NoCases, f, mean, xsqr, sumxy, S, X,
sumx, sumx2, N);
error := REDUCE(k1, r, T, C1, i5, rowtot, s5, f, S);
if error = 1 then exit;
FREQUENCIES(C1, r, f, rowtot, i5, s5, T, S );
v1 := 0.0;
v2 := 0.0;
GETLOGS(L, L1, L2, g, g2, f2, rowtot, k1, s5, S, T, r, C1, v1, v2);
EXPAND(v1, v2, xexpand, yexpand);
PROX(P, p2, k1, r, C1, L1, yexpand, xexpand, g, T, rowtot, i5, s5);
// start iterations for the maximum-liklihood (SetLengthton-Rhapson procedure)
// estimates
noloops := 0;
while (not finished) do
begin
d9 := MAXITEM(R1, d1, p1, D, e1, p2, P, S, rowtot, T, r, C1);
if (d9 < 0.01) then finished := true
else MAXABILITY(expdcnt, d2, e2, p1, p2, P, C1, r, D, s5, noloops);
noloops := noloops + 1;
if (noloops > 25) then
begin
ShowMessage('WARNING! Maximum Liklihood failed to converge after 25 iterations');
finished := true;
end;
end;
MAXOUT(r, C1, i5, s5, P, p2);
TESTFIT(r, C1, f, S, P, p2, T);
SLOPES(rptbis, rbis, slope, N, sumx, sumx2, sumxy, r, xsqr, mean);
ANALYZE(itemfail, grpfail, f, T, grppass, itempass, r, C1, min, max, p2);
if PlotItemsChk.Checked then PlotItems(r, i5, P);
if PlotScrsChk.Checked then PlotScrs(C1, s5, p2);
PLOTINFO(k1, r, info, A, slope, P);
FinishIt(r, i5, rptbis, rbis, slope, mean, itemfail, P);
// cleanup
A := nil;
info := nil;
D := nil;
p1 := nil;
f := nil;
grppass := nil;
grpfail := nil;
itempass := nil;
itemfail := nil;
i5 := nil;
s5 := nil;
S := nil;
sumxy := nil;
xsqr := nil;
mean := nil;
rowtot := nil;
X := nil;
d1 := nil;
R1 := nil;
p2 := nil;
P := nil;
f2 := nil;
g2 := nil;
g := nil;
L2 := nil;
L1 := nil;
L := nil;
e1 := nil;
expdcnt := nil;
d2 := nil;
e2 := nil;
slope := nil;
rbis := nil;
rptbis := nil;
ColNoSelected := nil;
end;
procedure TRaschFrm.InBtnClick(Sender: TObject);
VAR i, index : integer;
begin
index := VarList.Items.Count;
i := 0;
while i < index do
begin
if (VarList.Selected[i]) then
begin
ItemList.Items.Add(VarList.Items.Strings[i]);
VarList.Items.Delete(i);
index := index - 1;
i := 0;
end
else i := i + 1;
end;
OutBtn.Enabled := true;
end;
procedure TRaschFrm.OutBtnClick(Sender: TObject);
VAR index : integer;
begin
index := ItemList.ItemIndex;
if index < 0 then
begin
OutBtn.Enabled := false;
exit;
end;
VarList.Items.Add(ItemList.Items.Strings[index]);
ItemList.Items.Delete(index);
end;
procedure TRaschFrm.ANALYZE(VAR itemfail : IntDyneVec;
VAR grpfail : IntDyneVec;
VAR f : IntDyneMat;
VAR T : integer;
VAR grppass : IntDyneVec;
VAR itempass : IntDyneVec;
r, C1 : integer;
VAR min : double;
VAR max : double;
VAR p2 : DblDyneVec);
var
i, j : integer;
begin
for i := 0 to r-1 do itemfail[i] := 0;
for j := 0 to C1-1 do grpfail[j] := 0;
for i := 0 to r-1 do
begin
for j := 0 to C1-1 do
begin
grpfail[j] := grpfail[j] + f[i,j];
itemfail[i] := itemfail[i] + f[i,j];
end;
end;
T := 0;
for j := 0 to C1-1 do T := T + grpfail[j];
for j := 0 to C1-1 do grppass[j] := T - grpfail[j];
for i := 0 to r-1 do itempass[i] := T - itemfail[i];
min := p2[0];
max := p2[0];
for i := 0 to C1-1 do
begin
if (p2[i] < min) then min := p2[i];
if (p2[i] > max) then max := p2[i];
end;
end; // End Sub 'end analyze procedure
procedure TRaschFrm.EXPAND(v1, v2 : double;
VAR xexpand : double;
VAR yexpand : double);
begin
yexpand := sqrt( (1.0 + (v2 / 2.89)) / (1.0 - (v1 * v2 / 8.35)) );
xexpand := sqrt( (1.0 + (v1 / 2.89)) / (1.0 - (v1 * v2 / 8.35)) );
end; //End Sub 'end of expand
procedure TRaschFrm.FinishIt(r : integer;
VAR i5 : IntDyneVec;
VAR rptbis : DblDyneVec;
VAR rbis : DblDyneVec;
VAR slope : DblDyneVec;
VAR mean : DblDyneVec;
VAR itemfail : IntDyneVec;
VAR P : DblDyneVec );
var
i : integer;
outline : string;
begin
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add('Item Data Summary');
OutputFrm.RichEdit.Lines.Add( 'ITEM PT.BIS.R. BIS.R. SLOPE PASSED FAILED RASCH DIFF');
for i := 0 to r-1 do
begin
outline := format('%3d %6.3f %6.3f %5.2f %6.2f %4d %6.3f',
[i5[i],rptbis[i],rbis[i],slope[i],mean[i],itemfail[i],P[i]]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.ShowModal;
end; // end FinishIt procedure
procedure TRaschFrm.FREQUENCIES(C1, r : integer;
VAR f : IntDyneMat;
VAR rowtot : IntDyneVec;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec;
T : integer;
VAR S : IntDyneVec);
var
i, j, c2, c3 : integer;
Done : boolean;
outline, strvalue : string;
begin
Done := false;
c3 := C1;
c2 := 1;
if (c3 > 16) then c3 := 16;
while (not Done) do
begin
OutputFrm.RichEdit.Lines.Add('Matrix of Item Failures in Score Groups');
outline := ' Score Group';
for j := c2 to c3 do
begin
strvalue := format('%4d',[s5[j-1]]);
outline := outline + strvalue;
end;
outline := outline + ' Total';
OutputFrm.RichEdit.Lines.Add(outline);
OutputFrm.RichEdit.Lines.Add('ITEM' );
OutputFrm.RichEdit.Lines.Add('');
for i := 1 to r do
begin
outline := format('%4d ',[i5[i-1]]);
for j := c2 to c3 do
begin
strvalue := format('%4d',[f[i-1,j-1]]);
outline := outline + strvalue;
end;
strvalue := format('%7d',[rowtot[i-1]]);
outline := outline + strvalue;
OutputFrm.RichEdit.Lines.Add(outline);
end;
outline := 'Total ';
for j := c2 to c3 do
begin
strvalue := format('%4d',[S[j-1]]);
outline := outline + strvalue;
end;
strvalue := format('%7d',[T]);
outline := outline + strvalue;
OutputFrm.RichEdit.Lines.Add(outline);
OutputFrm.RichEdit.Lines.Add( '');
if (c3 = C1) then Done := true
else begin
c2 := c3 + 1;
c3 := c2 + 15;
if (c3 > C1) then c3 := C1;
end;
end; // end while not done
end; // end sub frequencies
procedure TRaschFrm.GETLOGS(VAR L : DblDyneVec;
VAR L1 : DblDyneVec;
VAR L2 : DblDyneVec;
VAR g : DblDyneVec;
VAR g2 : DblDyneVec;
VAR f2 : DblDyneVec;
VAR rowtot : IntDyneVec;
k : integer;
VAR s5 : IntDyneVec;
VAR S : IntDyneVec;
T, r, C1 : integer;
VAR v1 : double;
VAR v2 : double);
var
tx, rowtx, rx, t2, t3, e : double;
i, j : integer;
outline : string;
begin
t2 := 0.0;
tx := T;
rx := r;
for i := 0 to r-1 do
begin
rowtx := rowtot[i];
L[i] := ln(rowtx / (tx - rowtx));
t2 := t2 + L[i];
end;
t2 := t2 / rx;
for i := 0 to r-1 do
begin
L1[i] := L[i] - t2;
L2[i] := L1[i] * L1[i];
v1 := v1 + L2[i];
end;
v1 := v1 / rx;
OutputFrm.RichEdit.Lines.Add( 'Item Log Odds Deviation Squared Deviation');
for i := 0 to r-1 do
begin
outline := format('%3d %6.2f %6.2f %6.2f',
[i+1,L[i],L1[i],L2[i]]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
t3 := 0.0;
v2 := 0.0;
for j := 0 to C1-1 do
begin
e := s5[j];
g[j] := ln(e / (k - e));
g2[j] := S[j] * g[j];
t3 := t3 + g2[j];
f2[j] := S[j] * (g[j] * g[j]);
v2 := v2 + f2[j];
end;
t3 := t3 / tx;
v2 := v2 / (tx - (t3 * t3));
OutputFrm.RichEdit.Lines.Add('Score Frequency Log Odds Freq.x Log Freq.x Log Odds Squared');
for j := 0 to C1-1 do
begin
outline := format('%3d %3d %6.2f %6.2f %6.2f',
[s5[j],S[j],g[j],g2[j],f2[j]]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end; //end of getlogs
procedure TRaschFrm.GETSCORES(VAR noselected : integer;
VAR selected : IntDyneVec;
NoCases : integer;
f : IntDyneMat;
VAR mean : DblDyneVec;
VAR xsqr : DblDyneVec;
VAR sumxy : DblDyneVec;
VAR S : IntDyneVec;
VAR X : IntDyneVec;
VAR sumx : double;
VAR sumx2 : double;
VAR N : integer);
var
i, j, k1, T, item : integer;
outline, strvalue : string;
begin
OutputFrm.RichEdit.Clear;
OutputFrm.RichEdit.Lines.Add('Rasch One-Parameter Logistic Test Scaling (Item Response Theory)');
OutputFrm.RichEdit.Lines.Add('Written by William G. Miller');
OutputFrm.RichEdit.Lines.Add('');
k1 := noselected;
for i := 1 to k1 do
begin
for j := 1 to k1 + 2 do
begin
f[i-1,j-1] := 0;
end;
mean[i-1] := 0.0;
xsqr[i-1] := 0.0;
sumxy[i-1] := 0.0;
end;
for j := 1 to k1 + 2 do S[j-1] := 0;
N := 0;
sumx := 0.0;
sumx2 := 0.0;
//Read each case and scores for each item. Eliminate rows (subjects)
//that have a total score of zero or all items correct
for i := 1 to NoCases do
begin
if (not GoodRecord(i,noselected,selected)) then continue;
T := 0;
for j := 1 to k1 do
begin
item := selected[j-1];
X[j-1] := round(StrToFloat(Trim(OS3MainFrm.DataGrid.Cells[item,i])));
T := T + X[j-1];
end;
if ((T < k1) and (T > 0)) then
begin
outline := format('Case %3d Total Score := %3d Item scores',[i,T]);
sumx := sumx + T;
sumx2 := sumx2 + (T * T);
for j := 0 to k1-1 do
begin
mean[j] := mean[j] + X[j];
xsqr[j] := xsqr[j] + (X[j] * X[j]);
sumxy[j] := sumxy[j] + (X[j] * T);
strvalue := format('%2d',[X[j]]);
outline := outline + strvalue;
if (X[j] = 0) then f[j,T-1] := f[j,T-1] + 1;
end;
OutputFrm.RichEdit.Lines.Add(outline);
S[T-1] := S[T-1] + 1;
N := N + 1;
end
else begin
outline := format('case %3d eliminated. Total score was %3d',
[i, T]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end;
OutputFrm.RichEdit.Lines.Add('');
end; //end sub getscores
procedure TRaschFrm.MAXABILITY(VAR expdcnt : DblDyneVec;
VAR d2 : DblDyneVec;
VAR e2 : DblDyneVec;
VAR p1 : DblDyneMat;
VAR p2 : DblDyneVec;
VAR P : DblDyneVec;
C1, r : integer;
D : DblDyneMat;
VAR s5 : IntDyneVec;
noloops : integer);
var
i, j : integer;
d9 : double;
outline : string;
begin
d9 := 0.0;
outline := format('Maximum Likelihood Iteration Number %2d',[noloops]);
OutputFrm.RichEdit.Lines.Add(outline);
for j := 0 to C1-1 do
begin
expdcnt[j] := 0.0;
d2[j] := 0.0;
end;
for i := 0 to r-1 do
begin
for j := 0 to C1-1 do
p1[i,j] := exp(p2[j] - P[i]) / (1.0 + exp(p2[j] - P[i]));
end;
for j := 0 to C1-1 do
begin
for i := 0 to r-1 do
begin
expdcnt[j] := expdcnt[j] + p1[i,j];
// expected number in score group
D[i,j] := exp(p2[j] - P[i]) / (sqrt(1.0 + exp(p2[j] - P[i])));
d2[j] := d2[j] + D[i,j]; // rate of change value
end;
end;
for j := 0 to C1-1 do
begin
e2[j] := expdcnt[j] - s5[j]; // discrepency
e2[j] := e2[j] / d2[j];
if (abs(e2[j]) > d9) then d9 := abs(e2[j]);
p2[j] := p2[j] - e2[j];
end;
{ Debug check in old sample program
' writeln
' writeln('Actual and Estimated Scores')
' writeln
' writeln('Score Estimated Adjustment')
' for j := 1 to c1 do
' writeln(s5(j):3,' ',expdcnt(j):6:2,' ',e2(j):6:2)
' writeln
}
end; // end of maxability
function TRaschFrm.MAXITEM(VAR R1 : DblDyneVec;
VAR d1 : DblDyneVec;
VAR p1 : DblDyneMat;
VAR D : DblDyneMat;
VAR e1 : DblDyneVec;
VAR p2 : DblDyneVec;
VAR P : DblDyneVec;
VAR S : IntDyneVec;
VAR rowtot : IntDyneVec;
T, r, C1 : integer) : double;
var
i, j : integer;
d9 : double;
begin
d9 := 0.0;
for i := 0 to r-1 do
begin
R1[i] := 0.0;
d1[i] := 0.0;
end;
for i := 0 to r-1 do
for j := 0 to C1-1 do
p1[i,j] := exp(p2[j] - P[i]) / (1.0 + exp(p2[j] - P[i]));
for i := 0 to r-1 do
begin
for j := 0 to C1-1 do R1[i] := R1[i] + S[j] * p1[i,j];
e1[i] := R1[i] - (T - rowtot[i]);
end;
// e1(i) contains the difference between actual and expected passes
// now calculate derivatives and adjustments
for i := 0 to r-1 do
begin
for j := 0 to C1-1 do
begin
D[i,j] := exp(p2[j] - P[i]) / (sqrt(1.0 + exp(p2[j] - P[i])));
d1[i] := d1[i] + (S[j] * D[i,j]);
end;
e1[i] := e1[i] / d1[i];
// adjustment for item difficulty estimates
if (abs(e1[i]) > d9) then d9 := abs(e1[i]);
P[i] := P[i] + e1[i];
end;
{ debug check from old sample program
' writeln
' writeln('actual and estimated items right')
' writeln
' writeln('item actual estimated adjustment')
' for i := 1 to r do
' begin
' writeln(i:3,' ',(t-rowtot(i)):3,' ',e1(i):6:2)
' end
' writeln
}
Result := d9;
end; // end of maxitem subroutine
procedure TRaschFrm.MAXOUT(r, C1 : integer;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec;
VAR P : DblDyneVec;
VAR p2 : DblDyneVec);
var
i, j : integer;
outline : string;
begin
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add('Maximum Likelihood Estimates');
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add('Item Log Difficulty');
for i := 0 to r-1 do
begin
outline := format('%3d %6.2f',[i5[i],P[i]]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add('Score Log Ability');
for j := 0 to C1-1 do
begin
outline := format('%3d %6.2f',[s5[j],p2[j]]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end; // end of maxout
procedure TRaschFrm.PROX(VAR P : DblDyneVec;
VAR p2 : DblDyneVec;
k, r, C1 : integer;
VAR L1 : DblDyneVec;
yexpand, xexpand : double;
VAR g : DblDyneVec;
T : integer;
VAR rowtot : IntDyneVec;
VAR i5 : IntDyneVec;
VAR s5 : IntDyneVec);
var
tx, rowtx, errorterm, stderror : double;
i, j : integer;
outline : string;
begin
if ProxChk.Checked then OutputFrm.RichEdit.Lines.Add('');
for i := 0 to r-1 do P[i] := L1[i] * yexpand;
for j := 0 to C1-1 do p2[j] := g[j] * xexpand;
if ProxChk.Checked then
begin
OutputFrm.RichEdit.Lines.Add( 'Prox values and Standard Errors' );
OutputFrm.RichEdit.Lines.Add(' ');
OutputFrm.RichEdit.Lines.Add('Item Scale Value Standard Error');
end;
tx := T;
for i := 0 to r-1 do
begin
rowtx := rowtot[i];
errorterm := tx / ((tx - rowtx) * rowtx);
//writeln(lst,'row := ',i:2,' yexpand := ',yexpand:8:2,
// total := ',t:8,' row total := ',rowtot(i):8,
// error term := ',errorterm:8:2) end;
stderror := yexpand * sqrt(errorterm);
if ProxChk.Checked then
begin
outline := format('%3d %7.3f %7.3f',[i5[i],P[i],stderror]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end;
if ProxChk.Checked then
begin
outline := format('Y expansion factor := %8.4f',[yexpand]);
OutputFrm.RichEdit.Lines.Add(outline);
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add('Score Scale Value Standard Error');
end;
for j := 0 to C1-1 do
begin
stderror := xexpand * sqrt(k / (s5[j] * (k - s5[j])));
if ProxChk.Checked then
begin
outline := format('%3d %7.3f %7.3f',[s5[j],p2[j],stderror]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end;
if ProxChk.Checked then
begin
outline := format('X expansion factor = %8.4f',[xexpand]);
OutputFrm.RichEdit.Lines.Add(outline);
end;
end; //end of prox
Function TRaschFrm.REDUCE(k : integer;
VAR r : integer;
VAR T : integer;
VAR C1 : integer;
VAR i5 : IntDyneVec;
VAR rowtot : IntDyneVec;
VAR s5 : IntDyneVec;
VAR f : IntDyneMat;
VAR S : IntDyneVec) : integer;
var
Done : boolean;
check, i, j, column, row : integer;
outline : string;
begin // NOW REDUCE THE MATRIX BY ELIMINATING 0 OR 1 ROWS AND COLUMNS
OutputFrm.RichEdit.Lines.Add('');
//Store item numbers in i5 array and initialize row totals
for i := 0 to k-1 do
begin
i5[i] := i+1;
rowtot[i] := 0;
end;
//Store group numbers in s5 array
r := k;
T := 0;
C1 := k - 1; // No. of score groups (all correct group eliminated)
for j := 0 to C1-1 do
begin
s5[j] := j+1;
T := T + S[j];
end;
//Get row totals of the failures matrix (item totals)
for i := 0 to r-1 do
for j := 0 to C1-1 do rowtot[i] := rowtot[i] + f[i,j];
// now check for item elimination
Done := false;
while (not Done) do
begin
for i := 1 to r do
begin
if ((rowtot[i-1] = 0) or (rowtot[i-1] = T)) then
begin
outline := format('Row %3d for item %3d eliminated.',[i,i5[i-1]]);
OutputFrm.RichEdit.Lines.Add(outline);
if (i < r) then
begin
for j := i to r-1 do //move rows up to replace row i
begin
for column := 1 to C1 do
f[j-1,column-1] := f[j,column-1];
rowtot[j-1] := rowtot[j];
i5[j-1] := i5[j];
end;
end;
r := r - 1;
end; // end if
end; // end for i
check := 1;
for i := 0 to r-1 do
if ((rowtot[i] = 0) or (rowtot[i] = T)) then check := 0;
if (check = 1) then Done := true;
end;
// check for group elimination
Done := false;
j := 1;
while (not Done) do
begin
if (S[j-1] = 0) then
begin
outline := format('Column %3d score group %3d eliminated - total group count = %3d',
[j, s5[j-1], S[j-1]]);
OutputFrm.RichEdit.Lines.Add(outline);
if (j < C1) then
begin
for i := j to C1 - 1 do
begin
for row := 1 to r do
f[row-1,i-1] := f[row-1,i];
S[i-1] := S[i];
s5[i-1] := s5[i];
end;
C1 := C1 - 1;
end
else C1 := C1 - 1;
end;
if C1 = 0 then
begin
ShowMessage('Too many cases or variables eliminated');
OutputFrm.ShowModal;
Result := 1;
exit;
end;
if (S[j-1] > 0) then j := j + 1;
if (j >= C1) then
begin
while (S[C1-1] <= 0) do
begin
C1 := C1 - 1;
if C1 = 0 then
begin
ShowMessage('Too many cases or variables eliminated');
OutputFrm.ShowModal;
Result := 1;
exit;
end;
end;
Done := true;
end;
end;
outline := format('Total number of score groups := %4d',[C1]);
OutputFrm.RichEdit.Lines.Add(outline);
OutputFrm.RichEdit.Lines.Add('');
Result := 0;
end; // end of reduce
procedure TRaschFrm.SLOPES(VAR rptbis : DblDyneVec;
VAR rbis : DblDyneVec;
VAR slope : DblDyneVec;
N : integer;
sumx, sumx2 : double;
VAR sumxy : DblDyneVec;
r : integer;
VAR xsqr : DblDyneVec;
VAR mean : DblDyneVec);
var
propi, term1, term2, z, Y : double;
j : integer;
begin
z := 0.0;
term1 := N * sumx2 - sumx * sumx;
for j := 0 to r-1 do
begin
rptbis[j] := N * sumxy[j] - mean[j] * sumx;
term2 := N * xsqr[j] - (mean[j] * mean[j]);
if ((term1 > 0) and (term2 > 0)) then
rptbis[j] := rptbis[j] / sqrt(term1 * term2)
else rptbis[j] := 1.0;
propi := mean[j] / N;
if ((propi > 0.0) and (propi < 1.0)) then z := inversez(propi);
if (propi <= 0.0) then z := -3.0;
if (propi >= 1.0) then z := 3.0;
Y := ordinate(z);
if (Y > 0) then rbis[j] := rptbis[j] * (sqrt(propi * (1.0 - propi)) / Y)
else rbis[j] := 1.0;
if (rbis[j] <= -1.0) then rbis[j] := -0.99999;
if (rbis[j] >= 1.0) then rbis[j] := 0.99999;
slope[j] := rbis[j] / sqrt(1.0 - (rbis[j] * rbis[j]));
end;
end; // end of slopes procedure
procedure TRaschFrm.TESTFIT(r, C1 : integer;
VAR f : IntDyneMat;
VAR S : IntDyneVec;
VAR P : DblDyneVec;
VAR p2 : DblDyneVec;
T : integer);
var
ct, ch, prob : double;
i, j : integer;
outline : string;
begin
OutputFrm.RichEdit.Lines.Add('');
OutputFrm.RichEdit.Lines.Add( 'Goodness of Fit Test for Each Item');
OutputFrm.RichEdit.Lines.Add('Item Chi-Squared Degrees of Probability');
OutputFrm.RichEdit.Lines.Add('No. Value Freedom of Larger Value');
ct := 0.0;
for i := 0 to r-1 do
begin
ch := 0.0;
for j := 0 to C1-1 do
ch := ch + (exp(p2[j] - P[i]) * f[i,j]) + (exp(P[i] -
p2[j]) * (S[j] - f[i,j]));
prob := 1.0 - chisquaredprob(ch, T - C1);
outline := format('%3d %8.2f %3d %6.4f',[i+1,ch,(T-C1),prob]);
OutputFrm.RichEdit.Lines.Add(outline);
ct := ct + ch;
end;
OutputFrm.RichEdit.Lines.Add('');
end; // end of testfit
procedure TRaschFrm.PLOTINFO(k, r : integer;
VAR info : DblDyneMat;
VAR A : DblDyneMat;
VAR slope : DblDyneVec;
VAR P : DblDyneVec);
var
min, max, cg, hincrement, Ymax, elg, term1, term2, jx : double;
headstring, valstring : string;
i, j, jj, size : integer;
TestInfo : DblDyneMat;
begin
min := -3.5;
max := 3.5;
size := 0;
hincrement := (max - min) / 50;
SetLength(TestInfo,52,2);
cg := 0.2;
Ymax := 0;
for i := 1 to r do // item loop
begin
TestInfo[i-1,0] := 0.0;
TestInfo[i-1,1] := 0.0;
jj := 1;
jx := min;
while (jx <= (max + hincrement)) do
begin
if (slope[i-1] > 30) then slope[i-1] := 30;
elg := 1.7 * slope[i-1] * (P[i-1] - jx);
elg := exp(elg);
term1 := 2.89 * (slope[i-1]) * (1.0 - cg) * (slope[i-1]) * (1.0 - cg);
term2 := (cg + elg) * (1.0 + 1.0 / elg) * (1.0 + 1.0 / elg);
info[i-1,jj-1] := term1 / term2;
if (info[i-1,jj-1] > Ymax) then Ymax := info[i-1,jj-1];
jj := jj + 1;
jx := jx + hincrement;
end;
size := jj-1;
end;
for i := 1 to r do //item loop
begin
headstring := 'Item Information Function for Item ';
valstring := format('%3d',[i]);
headstring := headstring + valstring;
for j := 1 to size do
begin
A[j-1,0] := min + (hincrement * j );
A[j-1,1] := info[i-1,j-1];
TestInfo[j-1,1] := TestInfo[j-1,1] + info[i-1,j-1];
end;
if ItemInfoChk.Checked then plot(A, size, headstring, 50, 50);
end;
for j := 1 to size do TestInfo[j-1,0] := min + (hincrement * j );
headstring := 'Item Information Function for Test';
if TestInfoChk.Checked then PlotTest(TestInfo,size,headstring,50,50);
TestInfo := nil;
end; //end of PlotInfo
procedure TRaschFrm.plot(VAR xyarray : DblDyneMat;
arraysize : integer;
Title : string;
Vdivisions, Hdivisions : integer);
var
i : integer;
xvalue, yvalue : DblDyneVec;
begin
// Allocate space for point sets of means
SetLength(xvalue,arraysize);
SetLength(yvalue,arraysize);
SetLength(GraphFrm.Ypoints,1,arraysize);
SetLength(GraphFrm.Xpoints,1,arraysize);
// store points for means
for i := 0 to arraysize-1 do
begin
yvalue[i] := xyarray[i,1];
xvalue[i] := xyarray[i,0];
GraphFrm.Ypoints[0,i] := yvalue[i];
GraphFrm.Xpoints[0,i] := xvalue[i];
end;
GraphFrm.nosets := 1;
GraphFrm.nbars := arraysize;
GraphFrm.Heading := Title;
GraphFrm.XTitle := 'log ability';
GraphFrm.YTitle := 'Info';
// GraphFrm.Ypoints[1] := yvalue;
// GraphFrm.Xpoints[1] := xvalue;
GraphFrm.barwideprop := 0.5;
GraphFrm.AutoScaled := true;
GraphFrm.GraphType := 5; // 2d line chart
GraphFrm.BackColor := clYellow;
GraphFrm.WallColor := clBlack;
GraphFrm.FloorColor := clLtGray;
GraphFrm.ShowBackWall := true;
GraphFrm.ShowModal;
xvalue := nil;
yvalue := nil;
GraphFrm.Xpoints := nil;
GraphFrm.Ypoints := nil;
end; //end plot subroutine
procedure TRaschFrm.PlotItems(r : integer; i5 : IntDyneVec; P : DblDyneVec);
var
i : integer;
xvalues : DblDyneVec;
begin
SetLength(xvalues,r);
SetLength(GraphFrm.Ypoints,1,r);
SetLength(GraphFrm.Xpoints,1,r);
for i := 1 to r do
begin
xvalues[i-1] := i5[i-1];
GraphFrm.Xpoints[0,i-1] := xvalues[i-1];
GraphFrm.Ypoints[0,i-1] := P[i-1];
end;
GraphFrm.nosets := 1;
GraphFrm.nbars := r;
GraphFrm.Heading := 'LOG DIFFICULTIES FOR ITEMS';
GraphFrm.XTitle := 'ITEM';
GraphFrm.YTitle := 'LOG DIFFICULTY';
// GraphFrm.Ypoints[1] := P;
// GraphFrm.Xpoints[1] := xvalues;
GraphFrm.barwideprop := 0.5;
GraphFrm.AutoScaled := true;
GraphFrm.GraphType := 2; // bar chart
GraphFrm.BackColor := clYellow;
GraphFrm.WallColor := clBlack;
GraphFrm.FloorColor := clLtGray;
GraphFrm.ShowBackWall := true;
GraphFrm.ShowModal;
xvalues := nil;
GraphFrm.Xpoints := nil;
GraphFrm.Ypoints := nil;
end;
procedure TRaschFrm.PlotScrs(C1 : integer; s5 : IntDyneVec; p2 : DblDyneVec);
var
i : integer;
xvalues : DblDyneVec;
begin
SetLength(xvalues,C1);
SetLength(GraphFrm.Ypoints,1,C1);
SetLength(GraphFrm.Xpoints,1,C1);
for i := 1 to C1 do
begin
xvalues[i-1] := s5[i-1];
GraphFrm.Xpoints[0,i-1] := xvalues[i-1];
GraphFrm.Ypoints[0,i-1] := p2[i-1];
end;
GraphFrm.nosets := 1;
GraphFrm.nbars := C1;
GraphFrm.Heading := 'LOG ABILITIES FOR SCORE GROUPS';
GraphFrm.XTitle := 'SCORE';
GraphFrm.YTitle := 'LOG ABILITY';
// GraphFrm.Ypoints[1] := p2;
// GraphFrm.Xpoints[1] := xvalues;
GraphFrm.barwideprop := 0.5;
GraphFrm.AutoScaled := true;
GraphFrm.GraphType := 2; // bar chart
GraphFrm.BackColor := clYellow;
GraphFrm.WallColor := clBlack;
GraphFrm.FloorColor := clLtGray;
GraphFrm.ShowBackWall := true;
GraphFrm.ShowModal;
xvalues := nil;
GraphFrm.Xpoints := nil;
GraphFrm.Ypoints := nil;
end;
procedure TRaschFrm.PlotTest(VAR TestInfo : DblDyneMat;
arraysize : integer;
Title : string;
Vdivisions, Hdivisions : integer);
var
i : integer;
xvalue, yvalue : DblDyneVec;
begin
// Allocate space for point sets of means
SetLength(xvalue,arraysize);
SetLength(yvalue,arraysize);
SetLength(GraphFrm.Ypoints,1,arraysize);
SetLength(GraphFrm.Xpoints,1,arraysize);
// store points for means
for i := 1 to arraysize do
begin
yvalue[i-1] := TestInfo[i-1,1];
xvalue[i-1] := TestInfo[i-1,0];
GraphFrm.Ypoints[0,i-1] := yvalue[i-1];
GraphFrm.Xpoints[0,i-1] := xvalue[i-1];
end;
GraphFrm.nosets := 1;
GraphFrm.nbars := arraysize;
GraphFrm.Heading := Title;
GraphFrm.XTitle := 'log ability';
GraphFrm.YTitle := 'Info';
// GraphFrm.Ypoints[1] := yvalue;
// GraphFrm.Xpoints[1] := xvalue;
GraphFrm.barwideprop := 0.5;
GraphFrm.AutoScaled := true;
GraphFrm.GraphType := 5; // 2d line chart
GraphFrm.BackColor := clYellow;
GraphFrm.WallColor := clBlack;
GraphFrm.FloorColor := clLtGray;
GraphFrm.ShowBackWall := true;
GraphFrm.ShowModal;
xvalue := nil;
yvalue := nil;
GraphFrm.Xpoints := nil;
GraphFrm.Ypoints := nil;
end; //end plot subroutine
initialization
{$I raschunit.lrs}
end.