Many decades ago, psychologists discovered that comparisons of ...

[Kthamas]

Many decades ago, psychologists discovered that comparisons of young and old people revealed that cognitive functioning declined in old age when cross-sectional research was used.
 
  The same result did not appear with longitudinal research. The problem here is that the results in the cross-sectional research were affected by
  a. cohort effects.
  b. baseline effects.
  c. wave effects.
  d. trend effects.

Question 2

When research involves the simultaneous comparison of two different groups, it is termed
 
  a. multiple baseline research.
  b. cross-sectional research.
  c. longitudinal research.
  d. panel research.

[manuelcastillo]

Answer to Question 1

a

Answer to Question 2

b