1. direct
A relationship between two variables, in which changes in one variable are reflected in changes in the other variable
inverse
Positive (direct) Correlation
The variables go in the SAME direction
Negative (inverse) Correlation
The variables go in opposite directions.

2. Weaker is closer to zero
STRENGTH
OF RELATIONSHIP
Range: -1 to +1
Weaker is closer to zero
Scatterplot
the slope of the points suggests the direction of the relationship
the amount of scatter suggests the strength of the correlation
A number that measures the strength of a relationship.
Range is from -1 to +1
The relationship gets weaker the closer you get to zero
Which is a stronger correlation?
-.13 or +.38
-.72 or +.59
-.91 or +.04
Which relationship is stronger… A or B?

3. NEGATIVE

4. Correlational Research
There is a positive correlation between ice cream and murder rates.
Does that mean that ice cream causes murder?
What might account for this correlation?

6. Third or Missing Variable Problem
A relationship other than causal might exist between the two variables. It's possible that there is some other variable or factor that is causing the outcome. You don’t know this because you never controlled for those variables. 6

8. Perception of a relationship
Where none exist
Redelmeier and Tversky (1996) assessed 18 arthritis patients over 15 months, while also taking comprehensive meteorological data. Virtually all of the patients were certain that their condition was correlated with the weather.
In fact the actual correlation was close to zero.
A function of representativeness heuristic
What could be the possible explanation for this?

9. I need 10 female volunteers!
Stand in line according to your height!
Stand in line according to your shoe size!

10. Class Correlation Study
Question: Is there a correlation (relationship) between our shoe size and height?
Hypothesis: I predict that there will be a positive correlation between shoe size and height.
Population: Tosa West Students
Sample: 1st and 5th Hour Psychology Students

11. Is this a positive, negative, or no correlation?
Height
POSITIVE CORRELATION
SHOE SIZE
If correlation does not mean CAUSATION… what is the purpose of a correlation study?

12. Can you think of any correlations? Try looking some up later!

13.
BREAK BREAK BREAK

14. PRACTICE TIME
SZUZCZ

15. October 5th Agenda: STATISTICS… we will make it through
Learning Targets:
I will be able to understand the need for statistics
October 5th
Agenda:
STATISTICS… we will make it through
HOGWARTS, HOGWARTS, HOGGY,
HOGGY, HOGWARTS
Homework: MOD 8, Retakes --- DUE by Friday OCTOBER 5th, Test Monday, Midterm next week Thursday

16. Statistical Reasoning
Statistical procedures analyze and interpret data allowing us to see what the unaided eye misses.
A meaningful description of data is important in research. Misrepresentation may lead to incorrect conclusions.
OBJECTIVE 15| Explain the importance of statistical principles, and give an example of their use in daily life.
Psychology 7e in Modules

19. Measures of Central Tendency
A Skewed Distribution – representation of scores that lack symmetry around their average value

21. Measures of Variation
Range: The difference between the highest and lowest scores in a distribution.
ex. 3, 4, 6, 6, 7, 8, 8, 8, 9 again: 9 – 3 = 6
Standard Deviation: A computed measure of how much scores vary around the mean.
ex. Ms. Kong wants to see how consistent her dart scores are during the past 5 years.
OBJECTIVE 18| Explain two measures of variation.
Psychology 7e in Modules

22. If data is approx. normal, the data will follow these characteristics
Mean is: 490
SD is:
1 SD away from the mean is:
2 SD away from the mean is:
3 SD away from the mean is:
AP EXAM need to know % of scores that fall with 1,2,3 SD’s away from X

24. What is it?
Standard Deviation is the average distance measured from the average (mean) of a measured value.
Take the height of American males for example:
The average height of males in America is 5’10” with a standard deviation of 3”

25. Explanation
Most men fall within 3 inches of the 5’10” mark on either side
5’7”-6’1”
3” becomes the measure of SD
68% = 1 SD from mean
95-96% = 2 SD from mean
99% = 3 SD from mean -1
(-3”) +1
(+3”)

26. The more men you have on the 2 extremes, the higher the standard deviation
If there were 10,000 Yao Ming’s, and 10,000 Mini me’s, and very few men that were as tall as the boys in class, our average would still be 5’10”, but it wouldn’t be very representative of the American population-

27. Standard Deviation ****
Estimates the amount of dispersion around the mean.
The smaller the number, the more confident we can be that the mean is a good estimate of the group. Larger SD=more variability/dispersion of scores
To calculate SD: take the square root of the variance (which is found by subtracting each score from the mean, square each of these, add together and divide by # of scores).
(we do not need to calculate SD, just know what it means)

28. Standard Deviation
Say we have a bunch of numbers like 9, 2, 5, 4, 12, 7, 8, 11.
To calculate the standard deviation of those numbers:
Work out the Mean (the simple average of the numbers)
Then for each number: subtract the Mean and square the result
Then work out the mean of those squared differences.
Take the square root of that and we are done

29. SO…why know the SD?

33. What guidelines do psychological experiments use to stay
within ethical bounds?
What are Ethics?
What are ethics?
Ethics = methods of conduct for responsible behavior

34. Ethics
How far can an experiment go for the sake of breaking new ground in psychology?

35. APA Principles
Minimize possibility of misleading results – welfare and confidentiality of all participants = protected.
Responsible for dignity and welfare of participants
Obey all laws and regulations
Rights and responsibilities of participants and researchers determined before start of research

36. Human Research
Ethical research involving human subjects must meet the following requirements.
No coercion
Informed consent
Anonymity or confidentiality
Risk
Debriefing
"Human behavior is under situational control more than we imagine or want to believe and admit."
- Philip Zimbardo