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Information and Knowledge Management using ArcGIS ModelBuilder

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Hesbon Nyagowa, Dennis Ocholla <strong>and</strong> Stephen Mutula<br />

six schools were purposively included in the sample to provide insight into variation in the eSchools<br />

settings. Stratified probabilistic sampling of eSchool users was done to reduce the costs of data<br />

collection <strong>and</strong> yield results that could be inferred to the population (Guerrero, 2010). To reduce<br />

sampling error in the study an acceptably large sample was sought, <strong>and</strong> the variability of the sample<br />

characteristics was increased by <strong>using</strong> stratification within schools <strong>and</strong> between schools (Hussmann,<br />

Mehran & Varma, 1990). Stratification between schools was based on the population of eSchool<br />

users. Within each school, stratification was done at class level based on number of students in each<br />

class <strong>and</strong> the gender ratio in the case of co-education school.<br />

The respondents were spread across four levels of education (Forms I, II, III <strong>and</strong> IV). Each dimension<br />

of eSchool Success model was assessed <strong>using</strong> many question items. Blaikie (2009) observes that<br />

when many conditions have to be satisfied, the sample size should be made larger. With the average<br />

degree of freedom of 8 for each dimension, a power of alpha = 0.8, <strong>and</strong> the level of confidence of 0.05<br />

set for the current study, the desired sample size came to 754 (MacCallum, Browne & Sugawara,<br />

1996). To accommodate the use of a split-half in undertaking exploratory factor analysis, the ideal<br />

sample size was doubled to 1508. Data collected was triangulated from observations, interviews <strong>and</strong><br />

a questionnaire (Gupta, 2007). Observation was made on installed infrastructure <strong>and</strong> use of the<br />

eSchool. Interviews were conducted for school principals to get in-depth information on benefits of the<br />

eSchool <strong>and</strong> challenges encountered. The questionnaire facilitated collation of perception of eSchool<br />

users on different attributes of all the six dimensions of ESchool Success model. A total of 776<br />

completed questionnaires were returned. This constituted 51.4% response rate which is considerably<br />

high <strong>and</strong> is attributed to the h<strong>and</strong> delivery of the questionnaire (Maxfield <strong>and</strong> Babbie, 2008).<br />

4. Validation of instruments<br />

The study instruments stood the test of reliability <strong>and</strong> validity. Data was found to be stable in the splithalf<br />

exploratory factor analysis <strong>and</strong> had high reliability, with all dimensions recording an alpha value of<br />

0.7 <strong>and</strong> above apart from the ‘training for use effectiveness’ dimension which recorded alpha value of<br />

0.46. A scatter plot (figure 1) of the alpha from exploratory <strong>and</strong> confirmatory factor analysis show<br />

close correlation which confirms stability in the data sets. To validate the conceptualized seven<br />

dimensions of eSchool Success model, a scree plot of the possible factors was made <strong>and</strong> it revealed<br />

an elbow between five <strong>and</strong> nine component positions. The exact position of the elbow could be<br />

pinned to seven components as demonstrated in Figure 2.<br />

Figure 1: Scatter plots of test <strong>and</strong> confirmatory alpha<br />

Construct validity was established through factor analysis. Seven factors with many measurement<br />

items loading to them, in the same way as was theoretically conceptualised, were confirmed. These<br />

522

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