




































African Journal of Agricultural Marketing Vol. 2 (2), pp. 109-115, February, 2014. Available online at 
www.internationalscholarsjournals.org © International Scholars Journals 
 
 
 
 
 

Full Length Research Paper 
 

Justification of socio-economic condition as pointers 

for heads of farm families in Delta North agricultural 

zone, Delta State, Nigeria 
 

John D. Oghene 
 

Department of Agricultural Economics and Extension, Delta State University, Asaba Campus, Asaba, Nigeria. E-mail: 

john_oghene@yahoo.com. 
 

Accepted 29 January, 2014 
 

The specific objectives were to collate a universe of socio-economic condition pointers; carry out item 
analysis to validate socio-economic status indicators; select valid socio-economic status indicators for 
heads of farm families; and discuss the sociological implication of the valid items. Stratified and simple 
random sampling designs were used in selecting the towns and villages. Twelve percent of heads of 
farm families in selected Ibo speaking Local Government Areas of the state comprising Aniocha South 
(41), Ika South (47) Ndokwa West (55) and Oshimili North (31) were selected to give a sample size of 174 
heads of farm families. Structured interview schedules were used in data collection. Data were analysed 
using point-biserial correlation coefficient and t-test. A universe of 106 items were collated from a pre-
research survey. Sixty nine (69) items were found as valid indicators of socio-economic status. The 
number of relatives trained by the individual, axe, yam barn, motor cycle, motor car, bicycles and water 
cistern toilet had very important social and economic implications among the people. The indexes are 
recommended to development agencies for evaluating changes in socio-economic status of heads of 
farm families particularly after an agricultural development intervention programme. 

 
Key words: Indexes, item analysis, valid items, socio-economic status indicators, farm families. 

 
 
INTRODUCTION 
 
Item analysis is an empirical procedure for selecting valid 
items which could be used in construction of socio-
economic status scale as well as test and non test 
instrument. It involves selecting valid items from a 
universe of items based on a pre-determined criterion. 
Ebel (1972) and Gronlund (1976) stated that item 
analysis was a procedure used to find out items that 
might be too easy or difficult for the purpose of test 
construction. The process helps to identify items which 
failed to discriminate between the better and poor 
examinees. Several items analysis procedures have been 
used in the social and behavioural sciences. Grounlund 
(1976), Ebel (1972) and Ali et al. (1988) described the 
discrimination index procedure for selecting objective test 
items. The procedures are as follows: (1) Arrange the test 
scores or answer sheets in an order ranging from high to 
low; (2) Separate two groups of test papers, an upper 
consisting of approximately 27% of the total group who 
receive highest scores on the test and 

 
 
 

 
a lower group consisting of an equal paper from those 
who receive lowest scores; (3) Count the number of times 
each possible response to each item was chosen by the 
upper group. Do the same separately for the papers of 
the lower group; (4) Record the response counts opposite 
the responses they refer to on a copy of the test.; (5) Add 
the counts from the upper and lower groups to the keyed 
correct response; (6) Subtract this sum from the 
maximum possible sum, that is, the sum of the number of 
papers in upper and lower groups and divide the 
differences by the maximum possible. Express this as a 
percentage, that is, multiply the decimal fraction by one 
hundred (100), the result is an item difficulty; (7) Subtract 
the lower group count of correct responses from the 
upper group count of correct responses. Divide this 
difference by the maximum possible difference that is the 
number of papers in the upper (or lower) groups. This 
quotient expressed as a decimal fraction is called index of 
discrimination. 



Oghene              109 
 
 

 
This could be expressed mathematically as follows 

(Gronlund, 1976); 
 
DI = RU – RL 

½ T 
 
Where: 
 
DI =    Discrimination index 
RU = Number of persons in the upper group who got the 
item right. 
RL = Number of persons in the lower group who got the 
item right  
T = Total number of persons in both upper and lower 

group. 
 
The above procedure showed that the simple 
discrimination index procedure did not take into account 
the performance of an individual on total items in the test. 
An item analysis procedure such as the point-biserial 
correlation coefficient takes into cognizance the total test 
scores and an item response. Karabinus (1975), 
Henrysson (1976) and Kraemer (1981) remarked that the 
point-biserial correlation coefficient was used when an 
association existed between random variables X and Y, 
where X is a dichotomy and Y is measured on a 
continuum. The procedure involved simple tabular 
presentation of each test item to give the following 
information: (1) Number choosing the correct answer; (2) 
Number choosing the wrong answer; (3) Frequency 
distribution of criterion scores for the group choosing 
either of the options. The resulting Table would show that 
students with high criterion scores have a much stronger 
tendency to choose the right answer. They maintained 
that the relationship could be quantified by the use of the 
point-biserial correlation coefficient. Other statistical tools 
which could be used for item analysis included the 
tetrachoric correlation coefficient, t-test, Pearson r, 
multiple correlation and contingency Table. Divgi (1979) 
and Zalinski et al. (1979) explained that the tetrachoric 
correlation generally denoted by “rt”, was used to 
measure the degree of linear association between two 
variables X and Y where both were dichotomized and the 
true underlying distribution were assumed to be normal. If 
the underlying psychological traits of the dichotomous 
variables were normally distributed then the tetrachoric 
correlation coefficient is the product-moment correlation 
between the traits. It was difficult and time consuming 
because the formula was based on series of 
approximation. Akinola and Patel (1987) made use of the 
t-test in validating socio- economic status indicators. Total 
score on the scale was calculated by adding 2 or 1 for 
possession and non-possession, respectively for 75 
items. The scores were ranked from the highest to the 
lowest. The highest and lowest 25% of the farmers were 
then compared to see if there existed any significant 
difference in the proportion of farmers possessing the item 

 
 
 

 
at 0.01 level of significance. Gullickson and Hopkins 
(1976) maintained that the Pearson r was an extremely 
useful means of estimating the discrimination index of 
linear relationship between two variables for a given 
population. The Pearson r is a consistent and efficient 
estimator of p only under the conditions that r was 
obtained from a random sample of the population. 
Anderson et al. (1976) found that it was possible to relate 
one characteristic at the same time to more than two 
through multiple correlation coefficients. By this definition, 
the multiple correlation was the product – moment 
correlation between the predicted independent and best 
linear composite of the predictor variables. Most 
researchers especially in developing countries find it 
difficult to ascertain items that should be used to measure 
socio-economic status of farmers. Bills et al. (1985) 
observed that empirical research on the process of social 
stratification in developing nations has been hampered by 
the lack of adequate instrumentation and measurement 
procedures. This was not the case in industrialised 
nations where such instruments have been developed to 
a substantial level. This study, therefore, attempt at 
developing indexes of socio-economic status indicators 
for heads of farm families in the zone. The objectives of 
the study were to collate a universe of socio-economic 
status indicators; carry out item analysis to validate socio-
economic status indicators; select valid socio-economic 
status indicators for heads of farm families; and examine 
the social and economic importance of some valid socio-
economic status indicators. 
 
 
MATERIALS AND METHODS 
 
Sampling procedure and sample size 
 
Stratified and simple random sampling designs done on multi stage 
basis were used in selecting the respondents as well as the towns 
and villages. Delta North agricultural zone is inhabited by the Ibo 
speaking people. The 9 local government areas in Delta North 
Agricultural Zone were grouped into 4 on the basis of the old local 
government map and sub-ethnic groups. The selection was done in 
three stages. In the first stage, one local government area namely 
Aniocha South, Ika South, Ndokwa West and Oshimili North were 
randomly selected from each group. In the second stage, 40% of 
the towns Aniocha South (6), Ika South (6), Ndokwa west (6) and 
Oshimili North (4) were randomly selected. The third stage involved 
random selection of 12% of the heads of farm families and this 
corresponded to Aniocha South (41), Ika South (47), Ndokwa West 
(55) and Oshimili North (31). This gave a sample size of 174 

respondents. 

 
Data collection 
 
Oral interview and structured interview schedule were used in data 
collection. The interview schedule contained items which enhance 
individual’s socio-economic status in the agricultural zone. This was 
done by asking a few farmers in each of the local government areas 

to mention items that could enhance the socio-economic status of 
farm families. One hundred and twelve items were collated from the 
pre-research survey. These items were built into an interview 



110      Afr. J. Agric. Mark. 
 
 
 

Table 1. Evaluation of discrimination indexes after item analysis. 

 
 Index of discrimination Item evaluation 

 0.40 and above Very good item, accept 

 0.30 to 0.39 Reasonably good but subject to possible improvement 

 0.20 to 0.29 Marginal items, usually need and subject to improvement 

 Below 0.19 Poor items to be rejected or improved by revision 
 

Source: Ebel (1972). Essentials of educational measurement. 
 

 
schedule. 

The respondents were required to indicate possession, non-
possession or tick the number of items possessed in the case of 

quantitative items. The instrument was reliable. The reliability test 
showed a coefficient of (r = 0.88). Oral interview was used to elicit 
information related sociological implication of valid items. 

 
Data analyses 
 
A uniform scoring method which assigned a value of 1 for 
possession and 0 for non-possession was used for the 
measurement of dichotomous items. For quantitatively measured 
items, possession scores ranged from 0 to 6 depending on the 
number of items listed against the particular indicator.  
Gronlund (1976) suggested that items with average discriminating 

power usually fall around 0.58. Ebel (1972) stated various values of 
discriminating indexes and how to evaluate them (Table 1).  

A score was obtained for each individual following the above 
scoring procedure. The scores for all the respondents were 
arranged from low to high in order to form the criterion scores and 
the total for each criterion score were tabulated. The possession 
scores of the upper and lower 25% were compared by the use of t-
test at 0.01 level of significance for quantitative items (Table 2). 

Significant items were selected as valid. The point -biserial 
correlation coefficient was used in the item analysis of the 
dichotomous items. The criterion scores, number of possession, 
number of non-possession and total for each criterion score were 
tabulated. Items with rpbis 0.55 and above were selected as valid 
items (Table 3). 
 

 
RESULTS AND DISCUSSION 
 
Indexes of valid socio-economic status indicators in the 
Ibo ethnic group of Delta State Indexes of valid socio-
economic status indicators in the Ibo ethnic group of 
Delta State is given in Table 4. From the universe of 
socio-economic status indicators, 112 items were collated 
from the pre-research survey. These items were pre-
tested and ambiguous and localised items were removed. 
The items dropped were elephant tusk, mud house, pit 
toilet, granaries/silos, outside broom and cooking retort 
stand. These items were either possessed by very few 
persons or a particular socio-economic status group. 
After the pre-test, the universe of the socio-economic 
status indicators became 106 items. The pre-test was 
used to show items which did not discriminate or have 
zero discrimination. 

 

 
Valid socio-economic status indicators 
 
The results of the item analysis showed that 69 items 
were valid indicators of socio-economic status in the 
ethnic group (Table 2). The items were children in 
primary school, secondary school, tertiary school, number 
of relatives trained by the sponsor, cement house in the 
village, cement house outside the village, traditional hats, 
traditional attires, pair of shoes, George wrappers, single 
wrappers, room with cemented floor, chieftaincy title, 
cutlass, spades/shovel, water cistern toilet, wash hand 
basins, cabinets beds, wall hanger, framed photograph of 
oneself, axe, farm size, poultry, fish ponds, goats, hired 
labourers, yam barn, plots of land owned in the village, 
plots of land owned outside the village, personal 
borehole, motor cycle, motor car, compact disc player, 
radio/cassette player, television, ceiling/table fans, 
executive chairs, stove, GSM handset, personal 
generator, wheelbarrow, floor carpet, floor rug, wardrobe, 
rain coat, umbrella, book shelve, dinning table, metal 
buckets, plastic buckets, blender, frying pan, tumblers, 
kettle, bicycle, electric/coal iron, metal, spoons, 
suitcases/traveling bags, wash hand basins, glass plates, 
wrist watch, ability to read in English, ability to read native 
dialect, membership of social clubs, official in a Christian 
organization and membership of cooperative societies. 
These items could be standardized into a socio-economic 
status scale to measure the socio-economic status of 
heads of farm families in the Ibo ethnic group of Delta 
State, Nigeria. 
 
 
Social and economic implication of some valid items 
 
The valid items were cherished by the people socially, 
culturally and economically. A few of the items namely 
cutlasses, axes, yam barn, motor car, bicycle and number 
of relatives trained by a farmer have far reaching social 
and economic implication in the study area. 
 
 
Cutlasses and axes 
 
These two items were valid because they were the major 

tools used for farm labour. Beside the economic use, the 



Ovwigho 053 
Oghene              111 

 
 

 
Table 2. Item analysis procedure for quantitatively measured item using t-test 
 
  Item: Number of children in primary school    

Criterion scores 0 1 2 3 4 >4  Total 
           

 186       1  1 
 176     1  2  3 
 171     1  1  2 
 166   1    2  3 
 161     1    1 
 156     1    1 
 151    1     1 
 146       3  3 
 141       1  1 
 131    1     1 
 126  1  2     3 
 121    5  1   6 
 116    6 2 2   10 
 111    4 1    5 
 106   1 2  Upper (3) 25%   

 101   1 5 1    7 
 96    8     8 
 91   1 3 3 1   8 
 86    2 2    4 
 81    1 1 1   3 
 76    2 1 1   4 
 71   1  2    3 
 61   1 1 1 1   4 
 56  1  2  1   4 
 51   1 2 1 1   5 
 46  1 10 8 1 2   22 
 41  3 3 3 1 1   11 
 36  1 2 6  Lower (9) 25%   

 31  5 10 1 1    17 
 26  4 13 3     20 

Scores of upper  25% group who Possess the item = 
5,5,5,5,5,5,5,5,5,5,4,4,4,3,3,3,3,3,3,3,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1. Where N = 
43, x = 2.98. 
Scores of lower 25% group who possess the term = 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 

1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,3. Where N = 35, x = 1.34. 
 
t - ratio = 2.98 - 1.34 = 7.19 
 

0.2280 

 
But from Table 2, t = 2.660 at df= 76, p = 0.01. Decision = item is valid in the Ibo ethnic group 

since the observed t is higher than critical t. 
 

 
axe and cutlass were used during the Ikenga festival in 
Delta Ibo area of Delta State. Men come out to brandish 
cutlass ostensibly to demonstrate their physical prowess 
during the Ikenga festival which precedes the planting 
season around February/ March. 
 
 
Yam barn 
 
The yam barn is a local storage structure for yam. The 

 

 
Ibo ethnic group produces and consumes a lot of yam 
compared to other ethnic groups in Delta State. The 
number of yam barn is often used to assess the socio-
economic status and performance of a farmer in the pre-
ceding farming year. The new yam festival is performed 
by the people in September every year before the sales 
and consumption of the new crop. Igbokwe (2005) stated 
that no member of the Ibo community was allowed to 
consume and plant yams until the new yam festival and 
rituals for planting yams were performed. 



112      Afr. J. Agric. Mark. 

 
 
 

Table 3. Item analysis procedure for dichotomous item using point-biserial correlation. 
 

Item: Ownership of cement house(s) in the village  
 Criterion scores Yes (possession)  No (non-possession) Total 
 186 1   1 
 176 3   3 
 171 3   3 
 166 2 1 ` 3 
 161 11   11 
 156 1   1 
 151 3   3 
 146 1   1 
 141 1   1 
 131 3   3 
 126 6   6 
 121 8   8 
 116 3  2 5 
 111 1  2 3 
 106 5  2 7 
 96 6  2 8 
 91 5  2 7 
 86 2  3 5 
 81 1  2 4 
 76 1  2 3 
 71 1  2 3 
 61   2 2 
 56 1  4 5 
 51 1  3 4 
 46 1  4 5 
 41   21 21 
 36   11 11 
 31   9 9 
 26   17 17 
 21   20 2 
 Total (62)  (112)  

 
rpbis = MP - MN P (1-P) 

St 

 
Where: 

 
rpbis = symbol for point- biserial correlation 
MP = Mean score for heads of farm families who possessed the item was obtained by multiplying 
the scores on the yes column by the corresponding criterion score divided by N 
MN = Mean criterion score for heads of farm families who did not possess the item was obtained 
by multiplying the scores on the no column by the corresponding criterion score divided by N.  
ST = Standard deviation of the criterion scores  
P = Proportion of heads of farm families who possessed the item 

(Source: Adapted from Henrysson (1976). 
 

St = 43.42, MP = 117 .69, MN = 50.06, P = 
62

/ 174 = 0.36, 1 – p = 0.64 
 
 

rpbis = 117.69 – 50.06  
43.42 0.36(0.64) 

 
= 1.56 × 0.48 = 0.75 

 
Decision = the item is valid since the calculated rpbis is above 0.55 



Ovwigho 055 
Oghene              113 

 
 

 
Table 4. Indexes of valid socio-economic status indicators in the Ibo ethnic group of Delta State. 
 
  Item Statistical tool Discrimination index 
 1. Children in primary school t 7.19 
 2. Children in higher school t 3.53 
 3. Children in secondary school t 2.73 
 4. Number of relatives trained by you up to secondary school t 2.79 
 5. Ownership of cement house in the village rpbis 0.75 
 6. Ownership of cement house outside the village rpbis 0.65 
 7. Traditional hats t 5.54 
 8. Traditional attires t 11.70 
 9. Pair of shoes t 5.23 
 10. George wrappers t 6.63 
 11. Single wrappers t 2.72 
 12. Rooms with cemented floor t 29.56 
 13. Chieftaincy title rpbis 0.56 
 14. Cutlasses t 6.80 
 15. Spade/shovel t 6.80 
 16. Water cistern toilet rpbis 0.64 
 17. Wash hand basins rpbis 0.70 
 18. Cabinet beds t 5.18 
 19. Wall hanger rpbis 0.65 
 20. Framed photographs of yourself t 18.86 
 21. Axe rpbis 0.64 
 22. Farm size t 7.94 
 23. Poultry t 4.48 
 24. Fish ponds t 5.55 
 25. Goats t 5.36 
 26. Hired labourers rpbis 0.69 
 27. Yam barn ” 0.55 
 28. Plots of land owned in the village t 6.64 
 29. Plots of land owned outside the village rpbis 0.62 
 30. Personal bore- hole ” 0.74 
 31. Motor cycle ” 0.60 
 32. Motor cars ” 0.73 
 33. Turn table/speakers ” 0.70 
 34. CD Player ” 0.57 
 35. Television ” 0.65 
 36. Ceiling / Table fans ” 5.89 
 37. Executive chairs ” 0.74 
 38. Lantern t 14.25 
 39. Stove rpbis 0.55 
 40. Personal generator ” 0.59 
 41. Wheel barrow ” 0.75 
 42. Floor carpet ” 0.61 
 43. Rug ” 0.64 
 44. Wardrobe ” 0.58 
 45. Rain coat ” 0.63 
 46. Umbrella t 6,53 
 47. Book shelves rpbis 0.73 
 48. Refrigerator ” 0.58 
 49. Standing mirror ” 0.71 
 50. Dining table ” 0.78 
 51. Metal buckets t 10.67 



                                                 

  Table 4. Contd.   
      

   Item Statistical tool Discrimination index 
  52. Plastic buckets t 11.92 
  53. Electric blender rpbis 0.68 
  54. Frying pan ” 0.72 
  55. Tumblers t 16.08 
  56. Kettle ” 6.94 
  57. Bicycles rpbis 0.69 
  58 Electric/coal Iron ” 0.76 
  59 Metal spoons t 21.50 
  60. Suitcase/travelling bags t 3.15 
  61. GSM handset rpbis 0.53 
  62. Glass plates t 8.93 
  63. Wrist watch rpbis 0.69 
  64. Can you read English rpbis 0.55 
  65. Can you write English ” 0.55 
  66. Can you read your native dialect ” 0.67 
  67. Membership of social clubs ” 0.61 
  68. Official in a Christian organisation ” 0.59 
  69. Membership of co-operative societies t 9.73 
 

 
Motor cycle, cars and bicycles 
 
These three items were found valid in the Ibo ethnic 
group because they were the most popular means of 
transporting farm produce. Women and girls were often 
seen in this areas riding motor cycles and bicycles to 
farm. It was favoured means of transportation in the area 
because of its land-locked nature. 
 
 
Number of relatives educated or trained by the farmer 
 
The number of relatives trained by a farmer was a 
measure of socio-economic status and altruism in the Ibo 
ethnic group of Delta State. If an individual was wealthy 
and his relatives were not educated he is not usually 
accorded a pride of place in the Ibo speaking society of 
Delta State, In some cases, the individual might be given 
a chieftaincy title if he is able to train many of his 
relatives. In essence such an individual is respected for 
contributing his quota to the preservation of the African 
extended family system. 
 
 
Conclusion 
 
The empirical indicants for the measurement and 
construction of socio-economic status scale for farm 
families in the Ibo ethnic group of Delta State were 
established from the study. The 69 valid items play 
significant role in socio-economic lives of the farm 
families. Agricultural production like every other business 
venture is geared towards increase standard of living. 

 

 
Indexes of socio-economic status provide the basis for 

evaluating changes in socio-economic of farm families. 
On the whole, the use of the indexes generated in this 
study might reduce the arbitrary assignment of socio-
economic status to rural farmers in the study areas. 
 
 
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