to run a regression, regressing debt ratios against these variables, across the firms in a
industry:
Debt Ratio = α
0
+ α
1
Tax Rate + α
2
Pre-tax Returns + α
3
Variance in operating income
There are several advantages to the crosssectional approach. Once the regression
has been run and the basic relationship established (i.e., the intercept and coefficients
have been estimated), the predicted debt ratio for any firm can be computed quickly using
the measures of the independent variables for this firm. If a task involves calculating the
optimal debt ratio for a large number of firms in a short time period, this may be the only
practical way of approaching the problem, since the other chapters described in this
chapter are time intensive.
28
There are also limitations to this approach. The coefficients tend to shift over
time. Besides some standard statistical problems and errors in measuring the variables,
these regressions also tend to explain only a portion of the differences in debt ratios
between firms.
29
However, the regressions provide significantly more information than
does a naive comparison of a firm's debt ratio to the industry average.
Illustration 8.9: Estimating Disney’s debt ratio using the cross sectional approach
This approach can be applied to look at differences within a industry or across the
entire market. We can illustrate looking at the Disney against firms in the entertainment
sector first and then against the entire market.
To look at the determinants of debt ratios within the entertainment industry, we
regressed debt ratios of firms in the industry against two variables – the growth in sales
over the previous five years and the EBITDA as a percent of the market value of the firm.
Based on our earlier discussion of the determinants of capital structure, we would expect
firms with higher operating cashflows (EBITDA) as a percent of firm value to borrow
more money. We would also expect higher growth firms to weigh financial flexibility
28
There are some who have hypothesized that under-leveraged firms are much more likely to be taken over
than firms that are over-leveraged or correctly leveraged. If we want to find the 100 firms on the New York
Stock Exchange that are most under-leveraged, the cross-sectional regression and the predicted debt ratios
that come out of this regression can be used to find this group.
29
The independent variables are correlated with each other. This multi-collinearity makes the coefficients
unreliable and they often have signs that go counter to intuition.