The first attempt to meld many of these elements into an urban transportation planning process was in the Cleveland Regional Area Traffic Study in 1927, which was sponsored by the U.S. Bureau of Public Roads. But even in this study, traffic forecasting was a crude art using basically linear projections (Cron, 1975b).

The first attempt to meld many of these elements into an urban transportation planning process was in the Cleveland Regional Area Traffic Study in 1927, which was sponsored by the U.S. Bureau of Public Roads.
③これらの項目（要素）の多くを都市交通計画に取り込もうとする最初の試みは、1927年のクリーブランド地域交通調査であり、道路局(BPR)が支援していた。

But even in this study, traffic forecasting was a crude art using basically linear projections (Cron, 1975b).
④しかし、この調査でさえ、交通需要予測は基本的に線形モデル（予測）を用いた精度の低いもの（粗削りな手法）であった。(Cron, 1975b)

In the Boston Transportation Study, a rudimentary form of the gravity model was applied to forecast traffic in 1926, but the technique was not used in other areas. In fact, the 1930s saw little advancement in the techniques of urban transportation planning. It was during this period that the methodology of highway needs and financial studies was developed and expanded (U.S. Dept. of Transportation, 1979a).

In the Boston Transportation Study, a rudimentary form of the gravity model was applied to forecast traffic in 1926, but the technique was not used in other areas.
①1926年のボストン交通調査では、交通需要予測に初歩的な（形の）重力モデルの用いられたが、この手法は他の地域では使われなかった（採用されなかった）。

In fact, the 1930s saw little advancement in the techniques of urban transportation planning.
②実際、1930年代には、都市交通計画の手法にあまり（ほとんど）進歩が見られなかった。

It was during this period that the methodology of highway needs and financial studies was developed and expanded (U.S. Dept. of Transportation, 1979a).
③（ちょうど）この時期に、道路需要や財政分析に関する方法論が開発、発展した。(U.S. Dept. of Transportation, 1979a).