9th grade $16,322Some high school $19,095High school grad $25,081Some college(no degree) $29,903Associate's degree $31,358Bachelor's degree $41,361Master's degree $50,704Professional degree $76,659PhD $71,541

Nation X = TV's per capita Y = life exp. (years)

Angola 1/200 44Australia 1/2 76.5Cambodia 1/177 49.5Canada 1/1.7 76.5China 1/15 70Haiti 1/234 53.5Japan 1/1.8 79Russia 1/3.2 69UK 1/3 76USA 1/1.3 75.5Yemen 1/38 50

X = driving credit score Y = average incurred loss per policy(1-worst 10%, 2-next lowest 10%, … , 10-best 10%)1 $9182 $8463 $7914 $7075 $7036 $6817 $6318 $5849 $56810 $558

State X = avg. spending per student (in $) Y = mean SAT Math scoreAL 5,885 554AR 5,278 550FL 6,170 499GA 6,929 489LA 6,037 562MS 5,175 551NC 6,346 499SC 6,631 488TN 5,687 553

Team X = payroll (millions of $) Y = wins in 2005 regular seasonNYY 208.3 95BOS 123.5 95NYM 101.3 83LAA 97.7 95PHI 95.5 88STL 92.1 100SF 90.1 75SEA 87.7 69CHC 87.0 79ATL 86.5 90LAD 83.0 71HOU 76.8 89CHW 75.2 99BAL 73.9 74DET 69.1 71SD 63.3 82AZ 62.3 77CIN 61.9 73FL 60.4 83MIN 56.2 83TEX 55.8 79OAK 55.4 88WAS 48.6 81COL 48.2 67TOR 45.7 80CLE 41.5 93MIL 39.9 81PIT 38.1 67KC 36.9 56TB 29.7 67

Yankess = $2.18 millionTampa Bay = $440,000Phila = $1.08 million

How much $$ per win?

Cleveland best value for the money

Gathering Data:

•Experiments•Observations•Case Studies•Surveys•Longitudinal Studies•Cross-cultural studies

Samples:

•Small group of the tested population

•Must be representative of the larger population

•To avoid bias…

•Random Sample; individuals picked purely by chance (every individual has an equal chance of being selected)

•Stratified Sample; individuals deliberately chosen from various sub-groups of the population.

Ethnicity, age, sex, political/religious affiliation, etc

Size of sample is important for accuracy…

More data = better results!

Correlation; describes the degree of relatedness between two variables

•Positive correlation; both variables move in the same direction (both up OR both down)Ex. IQ and test scoresAttendance and gradesSchool cell phone use and detentions

Negative correlation; variables move in opposite directions.Ex. Brushing teeth and number of cavities.Life expectancy and smoking.

Children raised in homes with more appliances tend to perform better in school. Therefore, appliances improve intelligence.

Correlation does not imply causation

…but it can be used to make predictions.

=

education Lifetime earningpotential

Head Size (inches)

Height (inches)

1.Experiments• Control the situation, environment

• Decrease the influence of outside factors

• Hypothesis; educated guess…establish the foundation of the experiment

• Independent variable; the factor the experimenter changes to see its effect

• Dependent variable; the factor that is measured to see how it was affected by the independent variable

Controlled experiment:

Hypothesis: Red light helps plants grow better than blue light

24 hrs/day12 hrs/day

.5 liters of water/day20 degrees Celcius

1 liter of water/day15 degrees Celcius

Every factor other than the independent variable should remain CONSTANT!

Independent variable:Color of light

Dependent variable:Height of plant

Experimental group: gets the independent variable

Control group: gets treated exactly the same as the experimental group EXCEPT for the independent variable

Experimental results must be replicable. Results published in a journal then reviewed and critiqued by peers. If results can be replicated and the methods and conclusions accepted by the scientific community the results are accepted as either supporting or not supporting the hypothesis. You cannot really PROVE things in science!

One trap to avoid in research:

Self-fulfilling prophecy

The researcher finds what they expect to find and ignore or overlook other important facts, data, etc.

The researcher may do this unknowingly, which is why we publish results

Does a researcher’s beliefs, attitudes, or feelings affect the way he or she will interpret the results of an experiment?

If I work for an oil company or a utility company that uses coal, will I be as likely to believe in global warming, or will I only look at data that support what I already believe? (cherry picking the data)

Solution:

The Double-Blind Study

vs

Single-blind study: the test subjects are “blind”, but the researcher knows the Coke and Pepsi cups and could influence the results with body language, voice inflection, eye movements, etc. (intentional or not)

Double-blind study: both the test subjects and the researcher are “blind”. If neither know the products in the cups, no improper influence could affect the results.

2. Naturalistic Observation:

•To understand how the subjects behave naturally

•Avoid disturbing or interacting with the subjects

3. Case Studies:

•Intensive investigation of an individual or group•Usually focus on a particular problem or experience•Combine long-term observations (psychological tests, behavior reports, self-reports, etc)•Lacks a control group for comparison

4. Surveys

• Most practical way to gather data on attitudes, beliefs, and experiences from a large group of individuals quickly and easily.1. Interviews; allow modification of the

question if needed2.Questionnaires;

• Less time• Results more uniform• Eliminates influence of researcher

5. Longitudinal Studies

•Covers long periods of time

•Study and restudy the same group at regular intervals to determine changes in behavior

•Time consuming…good results may take years to obtain and publish

6. Cross cultural studies

•Comparisons of the way people in different cultures behave, think, feel, etc

•Certain values appear to be universal, but cultural differences do affect the development of moral reasoning.