This report describes standardized data for “Cowpea Yield Evaluation Trials - Rivers, 1990”. These data were standardized on 2024-09-20 by Robert Hijmans with this R script. The original data have a CC-BY license. Here you can download the standardized data.

This is the full citation of the data set:

Boukar, Ousmane; Christian Fatokun (1990). Cowpea Yield Evaluation Trials - Rivers, 1990. International Institute of Tropical Agriculture (IITA). Not versioned. doi:10.25502/20180920/1604/BO

The dataset has 64 records and 21 variables for cowpea in Nigeria. The dataset has 1 treatment(s): variety.


These are the first 25 records:

records
trial_id planting_date harvest_date on_farm is_survey rep crop variety yield_part yield N_fertilizer P_fertilizer K_fertilizer irrigated country location longitude latitude geo_from_source
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT87D-1629 seed 756.2 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IAR48W seed 196.0 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT86D-957 seed 919.1 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT87S-1462 seed 538.2 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT87S-1463B seed 292.6 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea L-80 seed 883.2 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea L-72 seed 910.8 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea K-39 seed 1576.0 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea -12AK seed 886.0 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea K-28 seed 626.5 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT86D-715 seed 557.5 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IAR-48 seed 943.9 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea H113-4 seed 1026.7 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IFE BROWN seed 667.9 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IAR11-48-2 seed 844.6 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 1 cowpea IT87D-1134 seed 1482.1 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea K-39 seed 839.0 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea L-80 seed 742.4 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea -12AK seed 736.9 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea IAR11-48-2 seed 507.8 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea IT86D-715 seed 240.1 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea IT86D-957 seed 1012.9 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea L-72 seed 568.6 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea H113-4 seed 673.4 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE
ANMD90RIVERS 1990-04-20 1990-10-05 FALSE FALSE 2 cowpea IAR48W seed 132.5 NA NA NA NA Nigeria Rivers 6.92091 4.85808 TRUE


The observations are for 1 locations, for which we have 1 unique mapped locations.


The standardization script does not emit non-compliance warnings.

The overall quality of the dataset, given the completeness of required variables was 5.6 on a scale of 10. See the table below

variable completeness (%)
planting_date 100
harvest_date 100
N_fertilizer 0
P_fertilizer 0
K_fertilizer 0
irrigated 0
latitude 100
longitude 100
location 100


The data are further summarized in the table below.

Variable Stats / Values Freqs (% of Valid) Graph Missing
trial_id [character] 1. ANMD90RIVERS
64(100.0%)
 0 (0.0%)
planting_date [character] 1. 1990-04-20
64(100.0%)
 0 (0.0%)
harvest_date [character] 1. 1990-10-05
64(100.0%)
 0 (0.0%)
on_farm [logical] 1. FALSE
64(100.0%)
 0 (0.0%)
is_survey [logical] 1. FALSE
64(100.0%)
 0 (0.0%)
rep [integer]
Mean (sd) : 2.5 (1.1)
min ≤ med ≤ max:
1 ≤ 2.5 ≤ 4
IQR (CV) : 1.5 (0.5)
1:16(25.0%)
2:16(25.0%)
3:16(25.0%)
4:16(25.0%)
 0 (0.0%)
crop [character] 1. cowpea
64(100.0%)
 0 (0.0%)
variety [character]
1. -12AK
2. H113-4
3. IAR-48
4. IAR11-48-2
5. IAR48W
6. IFE BROWN
7. IT86D-715
8. IT86D-957
9. IT87D-1134
10. IT87D-1629
[ 6 others ]
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
4(6.2%)
24(37.5%)
 0 (0.0%)
yield_part [character] 1. seed
64(100.0%)
 0 (0.0%)
yield [numeric]
Mean (sd) : 686.4 (303.3)
min ≤ med ≤ max:
121.4 ≤ 705.1 ≤ 1576
IQR (CV) : 358.9 (0.4)
 59 distinct values 0 (0.0%)
N_fertilizer [logical]
All NA's
 64 (100.0%)
P_fertilizer [logical]
All NA's
 64 (100.0%)
K_fertilizer [logical]
All NA's
 64 (100.0%)
irrigated [logical]
All NA's
 64 (100.0%)
country [character] 1. Nigeria
64(100.0%)
 0 (0.0%)
location [character] 1. Rivers
64(100.0%)
 0 (0.0%)
geo_from_source [logical] 1. TRUE
64(100.0%)
 0 (0.0%)