The first to introduce and analyse the concept of spurious—or nonsense—correlations was Udne Yule in 1926.[2]. Before the 1980s many economists used linear regressions on (de-trended[citation needed]
) non-stationary time series data, which Nobel laureate Clive Granger and Paul Newbold showed to be a dangerous approach that could produce spurious correlation,[3], [4], since standard detrending techniques can result in data that are still non-stationary.[5]. Granger's 1987 paper with Robert Engle formalized the cointegrating vector approach, and coined the term.[6]