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A nutrition store in the mall is selling an herbal supplement intended to influence memory. To test the effectiveness (i.e., the influence on memory) of the herbal mixture, a skeptical researcher obtains a sample of n = 49 people and requests that each person take the suggested dosage each day for 4 weeks. At the end of the 4-week period, each individual takes a standardized memory test (large numbers indicate better memory). The scores from the sample produced a mean of M = 33. In the general population, the standardized memory test is known to have a mean of µ = 30 and σ = 14. Do the sample data support the conclusion that the herbal supplement influenced memory? To answer this question, go through the 7 steps for hypothesis testing and use α = .05 (critical value = ±1.96). SHOW ALL YOUR WORK. 1) IV(s) and DV(s) and the number of tails: 2) State Hypotheses: 3) Describe where the critical region(s) would be on a distribution. 4) Calculate the z-score for the sample mean (if possible bold, underline, or indicate your final answer). 5) Decision: 6) Effect size: 7) Plain English interpretation and APA statistical information:

What is measured by the numerator of the z-score for a sample mean?

A normal distribution has a mean of µ = 80 with σ = 20. What score separates the lowest 30% of the distribution from the rest of the scores?

_____ refers to the match between a child’s temperament and the environmental demands the child must cope with.  

The belief that no single theory of development is adequate to explain the rich complexity of life-span development, while acknowledging that each has useful things to offer, reflects the _____ theoretical orientation.

Which is true of children in the preschool years?

The theory of _____ refers to awareness of presence and distinction between one’s own mental processes and the mental processes of others.  

A(n) _____ is a carefully regulated procedure in which one or more factors believed to influence the behavior being studied are manipulated while all other factors are held constant.  

A mother hands her baby a rattle, saying, “Here you are.” She then gently takes the rattle away, smiling and saying, “Thank you.” She does this repeatedly, letting the baby keep the rattle for several seconds each time and encouraging the baby to offer the rattle. Eventually, the baby takes the rattle, holds it for a few seconds, and then holds it out to her mother and smiles. This is an example of:  

If you subscribe to Paul Baltes’s perspective of life-span development, which of the following statements would you NOT agree with?