Observations in new variable that shouldn't be included

[Oscar Weinzettl]

Hello, I am trying to make a new variable with the following command

gen gift_group_test = 0 if gift_total < . & gift_received == 1
replace gift_group_test = 0 if gift_total > 0 & gift_total < 10000
replace gift_group_test = 1 if gift_total >= 10000 & gift_total < 100000
replace gift_group_test = 2 if gift_total > 100000
label define gift_group_test  0 "<10K" 1 "10k-100K" 2 "100K+"

Basically I want to order gifts people have received into 3 groups, below 10k, up to 100k and over 100k. I want to exclude any observations where the person received 0. However, for some reason certain observations are included where the gift received = 0. I thought I would exclude this via the set up. Gift_received == 1 means that the person states they have received a gift. Any idea why I have certain where gifts are == 0? Even if the person says they received a gift and then states the amount is = 0, shouldn't I still be able to exclude that observation by saying gift_total needs to be larger than 0 and smaller than 10k if it wants to be in group 0?

[Carlo Lazzaro]

Oscar:
at a very first glance, it may depend on the way you coded people who gift was=0. If they are coded as:
[CODE][
gift_received == 1 /CODE]

it may explain what you experienced:

. set obs 6


. g gift_total=. in 1


. replace gift_total=0 in 2


. replace gift_total=1000 in 3


. replace gift_total=100 in 4


. replace gift_total=100000 in 5


. replace gift_total=200000 in 6


. g gift_received=1 if gift_total!=.


. gen gift_group_test = 0 if gift_total < . & gift_received==1


. replace gift_group_test = 0 if gift_total > 0 & gift_total < 10000 & gift_received==1


. replace gift_group_test = 1 if gift_total >= 10000 & gift_total < 100000 & gift_received==1


. replace gift_group_test = 2 if gift_total > 100000 & gift_received==1


. label define gift_group_test  0 "<10K" 1 "10k-100K" 2 "100K+"

. label val gift_group_test gift_group_test

. list

    +--------------------------------+
     | gift_t~l   gift_r~d   gift_g~t |
     |--------------------------------|
  1. |        .          .          . |
  2. |        0          1       <10K |
  3. |     1000          1       <10K |
  4. |      100          1       <10K |
  5. |   100000          1       <10K |
     |--------------------------------|
  6. |   200000          1      100K+ |
     +--------------------------------+

.