To estimate a difference-in-differences it requires that one has a:
A. time series.
B. cross-sectional data set.
C. selected sample.
D. panel data set.
Answer: D
You might also like to view...
For gas exchange to occur quickly and efficiently, which type of epithelium must be present on all respiratory surfaces?
a. pseudostratified columnar epithelium b. simple squamous epithelium c. ciliated columnar epithelium d. stratified squamous epithelium e. ciliated squamous epithelium
The first kind of leukocyte lured to the site of inflammation is the
A. neutrophil. B. monocyte. C. macrophage. D. basophil.
Influenza virus adheres to the epithelium of the respiratory system with the aid of ________ and ________ found in its envelope spikes.
What will be an ideal response?
A twitch is contraction and relaxation of
A. one neuron. B. one muscle cell. C. an entire muscle. D. one sarcomere. E. several muscles.