Comparison of probability (simple random sampling) and non-probability sampling (convenience sampling) methods. R code for simulating a convenient sample, simple random sample, and compare bias and ...

1. Urban forest ecosystems confer multiple ecosystem services. There is therefore a need to quantify ecological characteristics in terms of community structure and composition so that benefits can be ...

Our third Methods 101 video explores some of the ways that nonprobability surveys differ from traditional probability-based polls. How do pollsters conduct surveys online and what does that mean for ...

By Courtney Kennedy, Andrew Mercer, Scott Keeter, Nick Hatley, Kyley McGeeney and Alejandra Gimenez As the costs and nonresponse rates of traditional, probability-based surveys seem to grow each year, ...