Dear Statalist,
I am experiencing an issue with the merge fucntion in Stata. I am trying to merge two data files based on a key identifier variable (Stkcd). The two datasets are matched but not matched on the key variable, instead the observations from the using file are simply added to the master file in the order in which they appear in the using file. Any idea why I may be having this issue. Thanks. I attache an example of my databelow (my matched variable is Stkcd)
Using
Command:
merge m:1 Stkcd using "using file name .dta"
Merged data:
I am experiencing an issue with the merge fucntion in Stata. I am trying to merge two data files based on a key identifier variable (Stkcd). The two datasets are matched but not matched on the key variable, instead the observations from the using file are simply added to the master file in the order in which they appear in the using file. Any idea why I may be having this issue. Thanks. I attache an example of my databelow (my matched variable is Stkcd)
| Master | ||||
| CompanyName1 | year | Stkcd | v1 | v2 |
| Bank A | 2015 | 1 | -2.13 | 1.11 |
| Bank A | 2016 | 1 | -0.10 | 2.08 |
| Bank A | 2017 | 1 | -7.13 | 0.29 |
| Bank A | 2018 | 1 | -1.25 | 1.27 |
| Bank A | 2019 | 1 | -0.91 | 0.44 |
| Bank A | 2020 | 1 | -1.02 | 0.92 |
| Bank A | 2021 | 1 | -1.55 | -0.11 |
| Bank B | 2015 | 2 | -2.07 | -0.09 |
| Bank B | 2016 | 2 | -3.67 | 0.41 |
| Bank B | 2017 | 2 | -6.12 | -0.33 |
| Bank B | 2018 | 2 | -0.51 | 1.68 |
| Bank B | 2019 | 2 | -1.16 | 0.66 |
| Bank B | 2020 | 2 | -1.34 | 1.29 |
| Bank B | 2021 | 2 | -6.26 | 0.75 |
| CompanyName2 | SecurityCode_A_StkCd | Stkcd |
| CompanyA | 333 | 333 |
| CompanyB | 338 | 338 |
merge m:1 Stkcd using "using file name .dta"
Merged data:
| CompanyName1 | year | Stkcd | v1 | v2 | CompanyNameA2 | SecurityCode_A_StkCd |
| Bank A | 2015 | 1 | -2.13 | 1.11 | CompanyA | 333 |
| Bank A | 2016 | 1 | -0.10 | 2.08 | CompanyA | 333 |
| Bank A | 2017 | 1 | -7.13 | 0.29 | CompanyA | 333 |
| Bank A | 2018 | 1 | -1.25 | 1.27 | CompanyA | 333 |
| Bank A | 2019 | 1 | -0.91 | 0.44 | CompanyA | 333 |
| Bank A | 2020 | 1 | -1.02 | 0.92 | CompanyA | 333 |
| Bank A | 2021 | 1 | -1.55 | -0.11 | CompanyA | 333 |
| Bank B | 2015 | 2 | -2.07 | -0.09 | CompanyB | 338 |
| Bank B | 2016 | 2 | -3.67 | 0.41 | CompanyB | 339 |
| Bank B | 2017 | 2 | -6.12 | -0.33 | CompanyB | 340 |
| Bank B | 2018 | 2 | -0.51 | 1.68 | CompanyB | 341 |
| Bank B | 2019 | 2 | -1.16 | 0.66 | CompanyB | 342 |
| Bank B | 2020 | 2 | -1.34 | 1.29 | CompanyB | 343 |
| Bank B | 2021 | 2 | -6.26 | 0.75 | CompanyB | 344 |
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