begin  comment Lineair regression with random coefficients,S 431,R 1279,program EAS 290666;
	integer tal,J1,J2,max,df;
	real    t,t1,P;

	comment	SP 131, see descr 28;
	real procedure tDistr(m,t);value m,t;integer m;real t;
	begin	integer i;
		real x,s,u,v;

		x:=arctan(abs(t)/sqrt(m));v:=cos(x)**2;
		if	m%2*2=m
		then	begin	s:=u:=sin(x)/2; i:=0 	end
		else	begin
				u:=4*arctan(1);s:=x/u;u:=sin(2*x)/u/2;
				if m>=3 then s:=s+u;i:=1
			end; 
		m:=m-2;
	L:	if i>=m then go to out;i:=i+2;u:=u*v*(i-1)/i;s:=s+u;go to L;
	out:	tDistr:= if t<=0 then .5-s else .5+s
	end tDistr;

	NLCR;PRINTTEXT("Result EAS 209666,band");ABSFIXT(10,0,read);tal:=read;

L:	NLCR;NLCR;ABSFIXT(10,0,read);NLCR;
	J1:=read;J2:=read;if J1 - J2 >= 0 then max:=J1 else max:=J2;

	begin	integer i,j,k,n,p;
		real   s1,s2,s3,s4;
		real array BB[1 : 2],b[1 : 2,1 : max];

		i:=0;
		for p:=J1,J2 do

		begin
			i:=i + 1;
			if i = 1 then PRINTTEXT("estimated slopes first sample")
			else PRINTTEXT("estimated slopes second sample");s4:=0;
			for j:=1 step 1 until p do

			begin
				n:=read;s1:=s2:=s3:=0;

				begin	real array x[1 : n];

					for k:=1 step 1 until n do begin	x[k]:=read;s1:=s1 + x[k]	end;
					s1:=s1 / n;
					for k:=1 step 1 until n do
					begin
						x[k]:=x[k] - s1;s2:=s2 + x[k] ** 2;s3:=s3 + x[k] * read
					end

				end;

				b[i,j]:=s3 / s2;NLCR;FLOT(6,2,b[i,j]);SPACE(3);FLOT(6,2,s2);s4:=s4 + b[i,j] / p

			end;	

			BB[i]:=s4

		end;

		t:=0;
		for j:=1 step 1 until J1 do begin	b[1,j]:=b[1,j] - BB[1];t:=t + b[1,j] ** 2	end;
		for j:=1 step 1 until J2 do begin	b[2,j]:=b[2,j] - BB[2];t:=t + b[2,j] ** 2	end;
		t:=(BB[1] - BB[2]) / t;t1:=J1 * J2 * (J1 + J2 - 2);t1:=t1 / (J1 + J2);t:=t * sqrt(t1);

		NLCR;PRINTTEXT("test for equality of slopes:  t=");FLOT(6,2,t);NLCR;
		df:=J1 + J2 - 2;PRINTTEXT("df= ");ABSFIXT(3,1,df);NLCR;
		P:=tDistr(df,t);PRINTTEXT("Pbr= ");FLOT(6,2,P)

	end;

	tal:=tal - 1;if tal > 0 then goto L
end