Changes in the Level of Literacy in a New Community of Early America
研究北卡罗来纳州Perquimans县自由人签名识字率的时间序列，发现呈U形模式，初期下降与政治社会动荡相关，后期上升与政治稳定及人口经济增长相关。
When arrayed in time series, the rates of signature literacy of free persons in colonial Perquimans County, North Carolina, exhibit the ∪-shaped pattern found in the records of many other new communities of early America. In Perquimans, the pattern was due to coincident movements in the literacy rates of immigrants and natives of the county. The initial drop was associated with pronounced political and social disorder; the rise, with improved political stability and with demographic and economic growth.