The world is in the midst of a huge fundamental shift in fibre supply, demand balances, and policy changes. Governments around the world are introducing policy changes which influence the supply demand balance as the politicians' thoughts are uttered. Government agencies and their bureaucrats are imposing changes on industry even before the legislation is passed by the government in question.
This ad hoc change process will continue for a time to come until the countries in question show a tough-mindedness with regard to their land use policies. Policies affecting forest areas such as protection areas, Native land claims, the protection of biodiversity and a true goal of sustainable development ; which addresses the combined issues of cultural, environmental, social and economic matters.
Eventually all of these difficult issues will reach essential closure. Then there will be great new opportunities for investment to meet the growing demand for forest products ; leading to a strengthening competitive position in the more traditional producing areas such as Canada.

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In many cases, the log-frequency vs magnitude curves for earthquakes show considerable curvature, though the well-known G-R (Gutenberg-Richter) formula predicts a straight line. To represent such data, two modifications of the G-R formula have been proposed.
log n(M)=a-bM M≤c
n(M)= M>c} ()
and log n(M)=a-bM+log(c-M) M<c
n(M)= M≥c} (3)
These are called here the truncated G-R formula and the modified G-R formula, respectively. These equations can be written in the form of probability density function:
(x)=/1--BCe^-Bx C≥x≥ ()
(x)=/-+--Bx(C-x) C>x≥ ()
where x=M-M_S, = ln 10, C=c-M_S, and M_S is the lower limit of magnitude above which the data is complete.
The estimation of and C in equation () by the method of moments was discussed by Okada (1970) and Cosentino et al. (1977). The equations proposed here are
expC(C-)/Cx-=--/- (16)
=(-C)/(-Cx) (15)
or /=-(+)/(e^BC-1)/1-/(e^BC-1) (18)
Bx=1-/(e^BC-1) (19)
The maximum likelihood method for equation () yields only one equation (equation (19), Page (1968), Okada (1970)). If we adopt C=Max(x_i) as the second equation, the C value is considerably biased. To correct the bias, a correction ΔC which is a function of and C is proposed. For this correction we must use some estimated values for and C.
To estimate and C in equation () by the method of moments the following equations are used.
/(-+-1){-(++)+-}/{-(+)+-}

2

(25)
Bx=

e

-

BC

(

BC

+

2

)+

BC

-

2

/

e

-

BC

+

BC

-1 (23)
The maximum likelihood estimates of

B

and C in equation (

6

) can be obtained by the equation:

2

-Bx=C/S ∑^S_i=1 1/C-x_i=

BC

(1-

e

-

BC

)/

e

-

BC

+

BC

-1 (27), (29)
The accuracy of

B

and C values determined by the above methods is estimated by Monte Carlo technique for the cases of S=50, 100, 200, 400, and 800 and several values of

B

and C. If we adopt the truncated G-R formula, the second method (which uses C=Max(x_i)+ΔC) gives more accurate C values, whereas the accuracy of

B

values is almost the same as that obtained by the method of moments. If we adopt the modified G-R formula, the maximum likelihood method gives more accurate

B

and C values than the method of moments. The η value (η=

x²

/

x²

) is a useful index for the deviation of the distribution of data from the G-R formula (for the G-R formula, theoretical value for η is

2

). An application of the present methods shows regional variations in

b

, c, and η values of shallow earthquakes in Japan.

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