Hello I have been struggling with this simple looking problem. I have two dataframes. The first one contains ID, date, and revenue information for specific suppliers.
id lastdate depvar A 5/10/2017 10 B 8/16/2017 20 C 2/14/2017 30 D 9/5/2017 40 E 8/1/2017 50 F 11/4/2017 60 G 6/22/2017 70 The second dataframe contains timeseries data of each supplier in different columns. For example Column A are the transaction dates of supplier A and A_indvar is an independent variable value for each date. A_date A_indvar B_date B_indvar … 1/1/2017 49 2/5/2017 50 1/2/2017 42 2/6/2017 62 1/3/2017 10 2/7/2017 88 1/4/2017 37 2/8/2017 36 1/5/2017 84 2/9/2017 71 1/6/2017 47 2/10/2017 36 1/7/2017 91 2/11/2017 98 Now, I would like to run a regression equation using specific independent variable values from the second dataset. For example, let say I want to look at the independent variable values of each supplier 30 days before the last date given in the first dataset. I want to locate those from the second dataset and enter them into the first dataset. So that the first dataset will look like: id lastdate depvar indvar-30 A 5/10/2017 10 55 B 8/16/2017 20 62 C 2/14/2017 30 74 D 9/5/2017 40 45 E 8/1/2017 50 35 F 11/4/2017 60 56 G 6/22/2017 70 48 I am able to create an array that takes all last dates and then subtracts 30 from them. Then how can I go to the second table and grab the value of the independent variables for those specific dates? Timeseries of the suppliers have different start dates. I feel like I need to use something similar to vlookup in Excel. But a value in the first dataset (let's say Supplier A) becomes a variable name in dataset two. Any hint is appreciated. Thank you. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.