Although it is a quick and non-expensive tool used to collect survey data in Egypt, the landline telephone surveys cannot reach the non-landline households, which makes up 73.4 percent of the households in Egypt according to the 2012/2013 Egypt – Household Income, Expenditure, and Consumption Survey (HIECS). Therefore, among other centers, the Public Opinion Poll Center (POPC) adopted the dual frame telephone surveys as an alternative to the landline telephone surveys, in which the landline sample is supplemented by a Pseudo-Random-Digit-Dial (Pseudo-RDD) sample of cell phones. The cell phone sample can reach the cell-only households (households with no landline but …

Sampling weights are a reflection of sampling design; they allow us to draw valid conclusions about population features from sample data. This paper explains the fundamentals of computing sampling weights for large-scale assessments in educational research. The relationship between the nature of complex samples and best practices in developing a set of weights to enable computation of unbiased population estimates is described. Effects of sampling weights on estimates are shown, as well as potential consequences of not using weights when analysing data from complex samples. Illustrative examples are provided in order to make it easy to understand the rationale behind …

Survey response rates for modern surveys using many different modes are trending downward leaving the potential for nonresponse biases in estimates derived from using only the respondents. The reasons for nonresponse may be complex functions of known auxiliary variables or unknown latent variables not measured by practitioners. The degree to which the propensity to respond is associated with survey outcomes casts light on the overall potential for nonresponse biases for estimates of means and totals. The most common method for nonresponse adjustments to compensate for the potential bias in estimates has been logistic and probit regression models. However, for more …

Correction of estimates of voting intention using voter recall of previous votes is frequent in electoral polls, particularly in Europe. However, research on the impact of its use is scarce. The results presented in this paper confirm that voting is not a salient, memorable behaviour for all voters. People who always vote the same way and identify with a political party are likely to accurately remember their vote, but in most developed countries, change of allegiance is now common. A substantial portion of the electorate changes its mind between or during campaigns, and switchers seem to have more difficulty remembering …