1. Research Methods in Psychology

2. Laboratory Field Internet Experimental Designs Randomization Manipulation Control Sample Population Independent Experimental Control Dependent Results Only research design that identifies cause-effect relationships

3. A study indicates that antioxidants found in blueberries may slow down the process of aging. In this study, 19-month old rats (equivalent to 60- year old humans) were fed either their standard diet or a diet supplemented by either: blueberry, strawberry, or spinach powder. After eight weeks, the rats were given memory and motor tests. Although all supplemented rats showed improvement, those supplemented with blueberry powder showed the most notable improvement. Can blueberries slow down aging? Can you identify the IV and DV?

4. Does beta-carotene protect against cancer? Beta-carotene supplements have been thought to protect against cancer. However, a study published in the Journal of the National Cancer Institute suggests this is false. The study was conducted with 39,000 women aged 45 and up. These women were randomly assigned to receive a beta-carotene supplement or a placebo, and their health was studied over their lifetime. Cancer rates for women taking the beta-carotene supplement did not differ systematically from the cancer rates of those women taking the placebo. Can you identify the IV and DV?

5. Does YX Correlational Designs CorrelationCoefficient 1 to -1.72 Strength of relationship +/- Direction of relationship Correlation does not prove causation + - Does X Y XYXY Z

6. A study of married couples showed that the longer they had been married, the more similar their opinions on social and political issues were. Positive or Negative? In a study of American cities, a relationship was found between the number of violent crimes and the number of stores selling violence-depicting pornography. A college professor found that the more class absences students have, the lower their grade in the course tends to be.

7. The Normal (Bell) Curve

8. Mean = average (2 + 3 / 2 = 2.5) (1, 2, 4, 5, 6 = 4) (1, 1, 4, 5 = 1) While the measures of central tendency are useful regarding typical scores, they do not provide information about the distribution of scores! Measures of Central Tendency Median = middle Mode = most frequent

9. The Concept of Statistical Analysis Statistical analyses conducted for only one of four reasons To describe data Are the groups actually different Are two or more variables related To reduce data All measures have naturally occurring variation Do different group averages represent real effects of just chance fluctuations? Various statistical tests allow us to estimate the likelihood of chance occurrences p <.05 Probability is less than 5 in 100 that the observed differences were a result of fate, karma, or chance.