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More Hypothesis Testing
model specified by the simple path diagram above specifies that the covariance (and
thus the correlation) between age and vocabulary is 0.
The second method of constraining a covariance parameter is the more general
procedure introduced in Example 1 and Example 2.
EFrom the menus, choose Diagram > Draw Covariances.
EClick and drag to draw an arrow that connects vocabulary and age.
ERight-click the arrow and choose Object Properties from the pop-up menu.
EClick the Parameters tab.
EType 0 in the Covariance text box.
EClose the Object Properties dialog box.
Your path diagram now looks like this: