soci332- statistics for social science

MODULE 1SOCI332- Statistics for Social Science

INTRODUCTION• Social research utilizes the scientific method to collect and analyze data

to determine what phenomena and dynamics are related to others. We look to study the relationships between two or more variables, how strong those relationships are, and whether they can be applied to the population they were drawn from.

• SPSS is a widely used statistical software program• Created and maintained by IBM

• Data sets are to SPSS as word documents are to Word.

WHAT IS STATISTICS?• A branch of mathematics that focuses on the

organization, analysis, and interpretation of a group of numbers• Two Main Branches of Statistics• descriptive statistics:

• used to summarize and describe a group of numbers from a research study• inferential statistics:

• procedures for drawing conclusions based on the scores collected in a research study but going beyond them

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THEORY OR HYPOTHESIS?• A theory is a general statement or set of

statements that describes and explains how different concepts are related to one another.

• A hypothesis is a tentative statement of expectation derived from a theory.• Proposes a relationship between two or more

variables• Independent and Dependent Variables

RESEARCH STRATEGIES

VARIABLES

Independent• The variable hypothesized to

“cause”, lead to, or explain the change in another variable- the dependent variable (DV)

Dependent• This is the variable that you are

watching to see changes in while you manipulate the independent variable (IV).

VARIABLES EXAMPLERead the following hypotheses and determine which part represents the independent variable and which represents the dependent variable.

1. Smoking causes cancer.

Independent Variable __________________Dependent Variable ____________________

Independent variable: smokingDependent variable: cancer

VARIABLES EXAMPLE 2Read the following hypotheses and determine which part represents the independent variable and which represents the dependent variable.

2. Women who breastfeed are less likely to have triple negative breast cancer.

Independent Variable __________________Dependent Variable ____________________

Independent variable: breastfeedingDependent variable: triple negative breast cancer

Let’s try another….

VARIABLE EXAMPLE #3Read the following hypotheses and determine which part represents the independent variable and which represents the dependent variable.

3. Men are more likely to read about the news over watching it on the Internet or other media source.

Independent Variable __________________Dependent Variable ____________________

(Whew, this is a tough one…)

Independent variable: genderDependent variable: method of consuming news media

LEVEL OF MEASUREMENT [CLICK TITLE TO VIEW VIDEO]

INTERVAL-RATIO Distance between categories is meaningful Ex. Income (measured in thousands of dollars); Age (measured in years)

ORDINAL Categories can be rank ordered Ex. Social class (lower, working, middle, upper); Attitudes towards gun control (strongly oppose, oppose, favor, strongly favor)

NOMINAL Categories differ in name Ex. Gender (male, female); Party Identification (Democrat, Republican

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ACTIVITY- LEVELS OF MEASUREMENT

Identify the level of measurement for the following variables. Are the following variables nominal, ordinal, or interval-ratio?1. Age2. Race3. Grade point average4. Person’s level of education (measured in achievement; high school,

some college, Bachelor’s degree, Master’s degree, PhD)5. Income

… Click to the next slide to check your answers.

ANSWERS1. Age – Interval-ratio2. Race – Nominal 3. Grade point average – Interval-ratio 4. Person’s level of education by achievement – Ordinal 5. Income – Interval-ratio

DISCRETE V. CONTINUOUSAlong with identifying the level of measurement each variable is, researchers also identify whether their variables are discrete or continuous.

Discrete• Values are completely separate of one

another• SPSS Ex. Number of siblings and SEX• Values or categories that cannot be

reduced or subdivided into smaller units or numbers

• Can be nominal, ordinal, or interval-ratio

Continuous• Values can be infinitely subdivided• SPSS Ex. AGE or EDUC (measured in

years)• Can either be interval-ratio or ordinal

BASIC CONCEPTS• Variable • characteristic or condition that can have different values

• e.g., level of stress• Value • possible number or category a score can have

• e.g., 0–10• Score • particular person’s value

• e.g., a study participant rates her current level of stress as a 5 on a scale of 0–10

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VARIABLES IN SPSS• Each variable contains two or more categories

• Each category has to be mutually exclusive and exhaustive

Variables CategoriesGender Men

WomenReligious involvement Involved

Not involvedSocial class Upper class

Middle classLower class

DESIGN YOUR RESEARCHYour research project and class assignments will use

data from the following data sets. Be sure to save these to your computer. You can also find them inside the

classroom.

• GSS 2012• DEMO.SAV• EXER.SAV