Hi everyone,

I'm working on a study to investigate the impact of firm performance on probability of takeover. I will be using a logit model, with target = 1 or 0 as the dependent variable, and other firm characteristics to obtain results. However, currently my ratio of targets to non-targets is 96 : 1315, which is quite skewed.

Hence, I'm looking to reduce my non-targets sample to a smaller number before running the regression, probably by matching 1-2 non-targets to every target. I plan to match the targets based on the year and reit_id but i'm not quite sure how to do this. Below is my code for a small portion of my data. The column target is the dependent variable, where i hope to reduce the number target = 0.

Thanks for your help in advance.


Code:
entityname    entityid    target    year    reit_id    roa    spalpha    ebitdamargin    market_ta
Campus Crest Communities, Inc.    4258761    1    2014    Specialty    .579    -0.51    37.455    40.21625
Monogram Residential Trust, Inc.    4190766    1    2016    Multifamily    .179    0.07    47.322    56.40852
Rayonier Inc.    4062541    0    2014    Specialty    1.811    -0.72    34.616    144.3895
CyrusOne Inc.    4332673    0    2014    Specialty    1.657    0.29    46.479    67.78162
American Residential Properties, Inc.    4383076    1    2014    Specialty    -.778    0.07    32.278    41.56983
Quality Care Properties, Inc.    4745972    1    2017    Health Care    2.141    -0.81    90.71    29.4966
New Senior Investment Group Inc.    4544851    0    2016    Health Care    .208    -0.09    41.152    28.49409
Gladstone Land Corporation    4264067    0    2014    Specialty    1.08    -0.92    50.964    54.68895
Independence Realty Trust, Inc.    4235858    0    2016    Multifamily    -.246    0.24    19.267    47.55272
Front Yard Residential Corporation    4345051    0    2015    Specialty    .982    -0.51    19.431    28.1446
Bluerock Residential Growth REIT, Inc.    4214866    0    2017    Multifamily    -1.42    -0.72    13.368    14.52915
New Senior Investment Group Inc.    4544851    0    2017    Health Care    1.07    -0.74    41.344    24.76231
Gladstone Land Corporation    4264067    0    2015    Specialty    1.552    -0.40    64.09    37.79842
Silver Bay Realty Trust Corp.    4335231    1    2016    Specialty    .954    0.07    44.124    49.76474
CatchMark Timber Trust, Inc.    4108902    0    2015    Specialty    -.518    -0.04    32.389    73.57886
Gladstone Commercial Corporation    4088076    0    2014    Diversified    2.586    -0.15    80.214    44.81316
Trade Street Residential, Inc.    4094472    1    2014    Multifamily    .444    0.46    40.342    49.62671
Gladstone Land Corporation    4264067    0    2016    Specialty    1.624    0.46    71.098    33.73792
Associated Estates Realty Corporation    103102    1    2014    Multifamily    1.62    0.61    51.628    91.29086
NexPoint Residential Trust, Inc.    4561930    0    2016    Multifamily    1.362    0.97    43.274    45.40438
NexPoint Residential Trust, Inc.    4561930    0    2017    Multifamily    .795    0.45    43.014    55.72662
UDR, Inc.    103025    0    2014    Multifamily    1.101    0.50    59.705    115.1405
CatchMark Timber Trust, Inc.    4108902    0    2016    Specialty    -.383    -0.09    30.576    61.54402
Gladstone Commercial Corporation    4088076    0    2015    Diversified    2.622    -0.29    82.294    41.37527
American Campus Communities, Inc.    4092925    0    2014    Specialty    1.721    0.41    48.367    76.2162
Mid-America Apartment Communities, Inc.    103123    0    2014    Multifamily    2.192    0.31    54.732    82.39773
Lexington Realty Trust    103128    0    2014    Diversified    2.94    0.06    81.272    68.14964
NorthStar Realty Europe Corp.    4608576    0    2016    Office    -.167    0.00    41.071    37.73274
Camden Property Trust    103094    0    2014    Multifamily    2.653    0.42    56.397    105.8357
Apartment Investment and Management Company    103180    0    2014    Multifamily    2.712    0.60    56.818    89.20546
Gladstone Land Corporation    4264067    0    2017    Specialty    1.822    0.48    73.489    40.06698
Global Net Lease, Inc.    4307540    0    2016    Diversified    1.613    -0.15    76.801    53.82782
Global Net Lease, Inc.    4307540    0    2017    Diversified    1.844    -0.53    78.085    45.57275
American Homes 4 Rent    4392539    0    2015    Specialty    .424    -0.11    43.443    51.29628
Pennsylvania Real Estate Investment Trust    102991    0    2014    Regional Mall    1.859    0.21    50.725    63.55355
One Liberty Properties, Inc.    102988    0    2014    Diversified    3.427    0.21    73.748    63.40358
Home Properties, Inc.    103183    1    2014    Multifamily    2.995    0.31    59.654    84.33441
Apartment Investment and Management Company    103180    0    2012    Multifamily    1.922    0.23    55.875    61.53297
New Senior Investment Group Inc.    4544851    0    2015    Health Care    -.109    -0.92    40.188    27.92127
MGM Growth Properties LLC    4674180    0    2017    Specialty    2.33    0.31    82.439    19.96539
Preferred Apartment Communities, Inc.    4263486    0    2012    Multifamily    1.318    0.52    46.964    33.54093
CatchMark Timber Trust, Inc.    4108902    0    2017    Specialty    -.21    0.18    29.093    77.03358
Rayonier Inc.    4062541    0    2015    Specialty    2.179    -0.38    36.139    117.6844
UDR, Inc.    103025    0    2012    Multifamily    .682    -0.20    59.412    86.96828
Wheeler Real Estate Investment Trust, Inc.    4305469    0    2014    Shopping Center    -1.892    -0.11    24.25    14.47827
Apartment Investment and Management Company    103180    0    2010    Multifamily    .972    1.07    48.615    41.19895
Preferred Apartment Communities, Inc.    4263486    0    2017    Multifamily    1.309    0.44    58.694    24.01128
Lexington Realty Trust    103128    0    2015    Diversified    2.936    -0.55    80.284    49.2753
Rouse Properties, Inc.    4298147    1    2015    Regional Mall    1.486    -0.33    56.213    33.42612
UDR, Inc.    103025    0    2013    Multifamily    .954    -0.47    59.396    86.26359
Colonial Properties Trust    103076    1    2012    Multifamily    1.977    -0.03    55.763    57.36412
QTS Realty Trust, Inc.    4405219    0    2014    Specialty    2.425    0.56    39.725    89.93388
Apartment Investment and Management Company    103180    0    2013    Multifamily    2.503    -0.52    56.902    62.18889
Washington Real Estate Investment Trust    103036    0    2014    Diversified    1.94    0.19    55.25    88.9749
AvalonBay Communities, Inc.    103145    0    2014    Multifamily    2.958    0.58    65.601    133.6737
Healthcare Realty Trust Incorporated    103057    0    2014    Health Care    2.364    0.45    59.304    97.91383
Gladstone Commercial Corporation    4088076    0    2012    Diversified    3.239    -0.06    83.093    35.79676
CoreSite Realty Corporation    4258680    0    2014    Specialty    2.757    0.28    46.367    79.06402
American Campus Communities, Inc.    4092925    0    2015    Specialty    1.654    -0.01    48.54    77.32224
Gladstone Commercial Corporation    4088076    0    2016    Diversified    2.455    0.50    81.015    60.98448
Digital Realty Trust, Inc.    4094311    0    2014    Specialty    2.63    0.52    55.927    94.38674
NorthStar Realty Finance Corp.    4092549    1    2015    Diversified    2.471    -0.93    47.505    20.25767
Apartment Investment and Management Company    103180    0    2015    Multifamily    2.616    0.13    57.883    102.2728
InfraREIT, Inc. (REIT)    4573482    0    2016    Specialty    3.656    -0.05    87.303    41.77341
Cogdell Spencer Inc.    4104525    1    2010    Health Care    1.354    0.08    25.996    46.61516
Camden Property Trust    103094    0    2016    Multifamily    2.639    0.11    56.562    122.0128
American Homes 4 Rent    4392539    0    2014    Specialty    -.017    -0.01    37.351    58.19209
Wheeler Real Estate Investment Trust, Inc.    4305469    0    2015    Shopping Center    -1.149    -1.50    45.911    41.35297
Pennsylvania Real Estate Investment Trust    102991    0    2016    Regional Mall    2.274    -0.41    55.312    50.39394
CIM Commercial Trust Corporation    4543503    0    2017    Office    1.073    0.63    36.596    62.57856
Equity Residential    103054    0    2014    Multifamily    2.515    0.59    64.383    113.581
Investors Real Estate Trust    107231    0    2013    Multifamily    2.9    -0.50    58.091    52.25985
Washington Real Estate Investment Trust    103036    0    2013    Diversified    1.988    -0.80    57.383    78.9179
PS Business Parks, Inc.    102999    0    2014    Diversified    3.514    -0.03    62.349    96.14012
Medical Properties Trust, Inc.    4095909    0    2014    Health Care    2.814    0.17    64.68    63.9744
UDR, Inc.    103025    0    2016    Multifamily    1.466    -0.13    62.788    126.9551
UDR, Inc.    103025    0    2010    Multifamily    .374    0.70    55.599    77.62515
American Assets Trust, Inc.    4270741    0    2014    Diversified    2.771    0.35    57.604    89.59715
Healthcare Trust of America, Inc.    4132396    0    2014    Health Care    1.928    0.53    61.652    111.1654
Wheeler Real Estate Investment Trust, Inc.    4305469    0    2017    Shopping Center    1.265    -0.77    58.985    19.0675
Pennsylvania Real Estate Investment Trust    102991    0    2017    Regional Mall    1.8    -0.98    54.761    32.14258
One Liberty Properties, Inc.    102988    0    2015    Diversified    3.369    -0.15    72.37    54.07995
Farmland Partners Inc.    4426904    0    2015    Specialty    1.424    0.03    50.33    38.09379
Washington Real Estate Investment Trust    103036    0    2015    Diversified    1.83    -0.01    56.267    84.21301
One Liberty Properties, Inc.    102988    0    2012    Diversified    3.33    0.36    75.484    61.89199
CBL & Associates Properties, Inc.    103092    0    2014    Regional Mall    3.824    0.02    65.297    50.10408