A researcher is concerned that the more he tries to control the variables in his experiment, the less he will be able to generalize his results to the "real world". At the same time, he is worried that if he makes his experiment more "natural" by measuring rather than manipulating variables, he may be unable to support a causal claim with his data. The researcher's dilemma reflects the tradeoff between: a) Construct and internal validity b) Construct and external validity c) Internal and external validity d) Internal and statistical validity |