Although, the permeability values obtained from Katz Thompson model were not accurate rather over-estimated for the composites under evaluation (Ma 2014; Ma et al. 2014) still the values could be used for comparative assessment.
As the observed change area typically is a result of a degradation of the forest cover rather than complete deforestation, we are likely to over estimate the amount timber volume logged per unit area.
These models are more difficult to interpret and are less powerful, since associations are estimated for each data collection point separately, rather than estimated linearly over time.
This might have affected the results on the between-group differences, but the bias would be more likely to under-estimate rather than over-estimate the difference.
As generally untreated patients have a higher probability of death or readmission the resulting values most likely under- rather than over-estimate the calculated expected impact.
Indeed, our experience suggests that a search strategy like the one we used is likely to under-estimate rather than over-estimate the prevalence of rheumatic disease in the IHS user population.
It is therefore possible that more severe cases of women who might not be able to get pregnant, even after fertility treatment, were not included; if this were the case our estimates of fertility treatment and twin births are likely to be under- rather than over-estimates.
However, because we used actual values of X Y ordered pairs to estimate the general distribution of victimizations over possible victims, rather than estimated coefficients (as is standard in meta-analysis), it is unclear if weights improve the validity of our analysis.
It has been argued that self-report questionnaires tend to err on the side of high sensitivity rather than high specificity, and tend to over-estimate the prevalence of psychiatric disorders [ 96, 97].
However, some comments revealed student perceptions that parents could over-estimate their child's ability rather than give an objective assessment.
The approach to our needs assessment is conservative: in the face of uncertainty and a number of inestimables described above, it will under-rather than over-estimate need.
