**Chapter 2: Research Methodology**

**Scientific Method **

** Hypothesis/Formulate
a question**

** Method/Develop
a way to test the question**

** Results**

** Conclude**

** Report**

**Quantitative Method (Positivist Social Science)**

**Qualitative Method (Interpretive Social Science)**

** **

**General Principles of Conducting Psychological
research**

** Operational
Definition**

** Samples
of the Population (4)**

** Generalizing/validity**

** Objective
Measurement**

** Experimenter
Bias/Blind Studies**

** Blind
Observer**

** Reliability
**

** Multiple
Measures (concept)**

** **

**Observational or Descriptive Research Designs**

** Naturalistic
Observation**

** Survey
Method**

** Case
Histories **

** Correlation
**

** Correlation
Coefficient (r)**

**Rules for Correlation**

**1.
****Positive
or Negative = Direction of effect/relationship**

**2.
****Range
(one to negative one) = Size of effect/relationship**

**3.
****r
= 0, then there is NO relationship or the relationship is random**

**4.
****Correlation
DOES NOT EQUAL causation **

**Correlations:
Positive or Negative?**

**For each of the correlations described below,
determine the direction (positive or negative).**

**1. A
study of married couples showed that the longer they had been married the more
similar their opinions on social and political issues were.**

**2. An
intelligence test was given to all the children in an orphanage. The results showed that the longer the children
had lived in the orphanage, the lower their IQ scores.**

**3. In**** a study of American cities, it was found that as the number of
violent crimes increase so did the number of stores selling violence-depicting
pornography.**

**4. A
college professor found that the more class absences students have, the lower
their grade in the course tends to be.**

**5. A
politician running against a candidate who has been in office for eight years
pointed out that violent crime had increased steadily during those eight years
while the administration appropriated more and more money to fight crime.**

**6. It was
found that elementary school children scored highly on a vocabulary test also
tended to score highly on a test of physical strength and muscular
coordination.**

**7. In**** golf, the better one’s ability, the lower one’s score.**

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**Experiments**

**Independent Variables and Dependent Variables**

** A
condition is a level of the independent variable. **

** Experimental
Group, Control Group, and Random Assignment **

**How experiments can go wrong: Demand Characteristics**

**Ethical Considerations in Experimentation**

**The key question to be answered here is when is
the researcher justified in risking harm (physical or otherwise) for the sake
of knowledge?**

**Measuring and Analyzing Results **

**Descriptive Statistics: Descriptive Statistics
are “Mathematical summaries of results.”**

**1.
Measurements of the Central Score:
Mean, Median, and Mode.**

** a. the mean is the
“sum of all the scores divided by the total number of scores.” It is the most useful measure, especially if
the scores approximate a normal distribution.**

** b. A normal
distribution is “a symmetrical frequency of scores clustered around the
mean."” The mean can be misleading if the distribution is not normal. **

** c. The median is the
middle score of a distribution, and is affected less by extreme scores.**

** d. The mode is “the
score that occurs most frequently.”**

**2. Measures of variation: To**** fully capture a distribution, we also need some
measurement of spread around the mean. **

** **

** a. One such measure,
the range, is simply “a statement of the
high and low scores.” It is not very
useful because it only reflects the extremes.
**

** b. The standard deviation is “a measurement of
the amount of variation among scores in a normal distribution”, and provide a useful means of comparing
scores on two different tests (which tests **).**

**Evaluating Results: Inferential Statistics**

**1. The
95% confidence interval is “the range within which it is 95% certain that the
true population lies. “ It is an example
of an inferential statistic, “a statement about a large group based on an
inference from a small sample.” The
usual convention is that the probability that a result occurred due to chance
is less that 5%, that the result is considered “statistically significant.”**