Question

For each research project listed here, identify the variables and classify them in terms of level of measurement and whether they are independent or dependent. a. For a research project in a political science course, a student collected information for 50 nations. She used infant mortality rates (the number of infant deaths per 100,000 population) as a measure of quality of life and the percentage of all adults who are permitted to vote as a measure of democratization. Her hypothesis was that quality of life is higher in more democratic nations. b. A highway engineer wonders whether increasing the speed limit on a heavily traveled highway will result in more accidents. He plans to collect information on traffic volume, number of accidents, and number of fatalities for the sixmonth periods before and after the speed limit is changed. c. Students are planning a program to promote "safe sex" and awareness of other health concerns on campus. To measure the effectiveness of the program, they plan to survey students about their knowledge of safe sex practices before and after the program. d. A graduate student asks 500 female students whether they have experienced any sexual harassment on campus. Each student is asked to estimate the frequency of these incidents as either "often, sometimes, rarely, or never." The researcher also gathers data on age and major to see whether there is any connection between these variables and frequency of sexual harassment. e. A supervisor in the solid waste management division of city government is assessing two different methods of trash collection. One area of the city is served by trucks with two-man crews who do "backyard" pickups, and the rest of the city is served by "high-tech" single-person trucks with curbside pickup. The assessment measures include the number of complaints received from the two different areas over a six-month period, the amount of time per day required to service each area, and the cost per ton of trash collected. f. Does tolerance for diversity vary by race or ethnicity? Samples of white, black, Asian, Hispanic, and Native Americans have been given a survey that measures their interest in and appreciation of cultures other than their own. Degree of tolerance is scored as "high, moderate, or low." g. States have drastically cut their budgets for mental health care. Will this increase the number of homeless people? A researcher contacts a number of agencies serving the homeless in each state and develops an estimate of the size of the homeless population before and after the cuts. h. The adult bookstore near campus has been raided and closed by the police. Your social research class has decided to poll a sample of students to find out whether he or she supports the store's closing, how many times each has visited the store, and whether he or she agrees that "pornography causes sexual assaults on women." The class also collects information on the gender, political philosophy, and major of the students to see if these characteristics affect opinions.

Short answer

Identify and classify variables for each situation, focusing on dependent/independent status and level of measurement.

Step-by-step solution

- Identify Variables for Situation a

For the political science project, identify the variables: infant mortality rates (quality of life) and percentage of adults permitted to vote (democratization).

- Classify Variables for Situation a

1. Infant mortality rates: Dependent Variable, Ratio Level of Measurement2. Percentage of adults permitted to vote: Independent Variable, Ratio Level of Measurement

- Identify Variables for Situation b

For the highway engineer's project, identify the variables: traffic volume, number of accidents, number of fatalities, and speed limit.

- Classify Variables for Situation b

1. Traffic volume: Control Variable, Ratio Level of Measurement2. Number of accidents: Dependent Variable, Ratio Level of Measurement3. Number of fatalities: Dependent Variable, Ratio Level of Measurement4. Speed limit: Independent Variable, Interval Level of Measurement

- Identify Variables for Situation c

For the safe sex program project, identify the variables: student knowledge of safe sex practices before and after the program.

- Classify Variables for Situation c

1. Student knowledge before the program: Dependent Variable, Ordinal Level of Measurement2. Student knowledge after the program: Dependent Variable, Ordinal Level of Measurement3. Safe sex program: Independent Variable, Nominal Level of Measurement

- Identify Variables for Situation d

For the research on sexual harassment, identify the variables: frequency of sexual harassment, age, and major.

- Classify Variables for Situation d

1. Frequency of sexual harassment: Dependent Variable, Ordinal Level of Measurement2. Age: Independent Variable, Ratio Level of Measurement3. Major: Independent Variable, Nominal Level of Measurement

- Identify Variables for Situation e

For the trash collection assessment, identify the variables: number of complaints, amount of time per day required, cost per ton, and method of trash collection.

- Classify Variables for Situation e

1. Number of complaints: Dependent Variable, Ratio Level of Measurement2. Amount of time per day required: Dependent Variable, Ratio Level of Measurement3. Cost per ton: Dependent Variable, Ratio Level of Measurement4. Method of trash collection: Independent Variable, Nominal Level of Measurement

- Identify Variables for Situation f

For the diversity tolerance survey, identify the variables: race/ethnicity and degree of tolerance.

- Classify Variables for Situation f

1. Race/Ethnicity: Independent Variable, Nominal Level of Measurement2. Degree of tolerance: Dependent Variable, Ordinal Level of Measurement

- Identify Variables for Situation g

For the mental health budget cuts project, identify the variables: number of homeless people and budget cuts.

- Classify Variables for Situation g

1. Number of homeless people: Dependent Variable, Ratio Level of Measurement2. Budget cuts: Independent Variable, Nominal Level of Measurement

- Identify Variables for Situation h

For the bookstore closing survey, identify the variables: support for store's closing, number of visits to store, opinion on pornography, gender, political philosophy, and major.

- Classify Variables for Situation h

1. Support for store’s closing: Dependent Variable, Nominal Level of Measurement2. Number of visits to the store: Dependent Variable, Ratio Level of Measurement3. Agreement that 'pornography causes sexual assaults on women': Dependent Variable, Ordinal Level of Measurement4. Gender: Independent Variable, Nominal Level of Measurement5. Political philosophy: Independent Variable, Nominal Level of Measurement6. Major: Independent Variable, Nominal Level of Measurement

Key concepts

Independent Variables

Independent variables are the factors that researchers manipulate or consider to determine their effects on dependent variables. In social research, these variables are often seen as the causes or predictors of outcomes. For example, in Situation a from the exercise, the percentage of adults permitted to vote was the independent variable, hypothesized to affect the quality of life. Identifying independent variables correctly is crucial, as they form the basis for understanding how different factors influence social phenomena.
Common types of independent variables:

• Demographic factors (e.g., age, gender)
• Policy changes (e.g., speed limits)
• Interventions (e.g., educational programs)

Knowing how to correctly identify and classify these variables is essential for valid research conclusions.

Dependent Variables

Dependent variables are the outcomes that researchers are interested in explaining or predicting. They depend on the influence of independent variables. For instance, in Situation b, the number of accidents and fatalities were dependent variables, influenced by the independent variable (speed limit).
Dependent variables help measure the effect or result of changes in one or more independent variables. They provide the data needed to test hypotheses and draw conclusions in social research.

• Examples include rates of accidents, test scores, health outcomes
• They are often measured at various levels, such as nominal, ordinal, interval, or ratio

Correct classification of dependent variables helps in the accurate analysis of research data.

Level of Measurement

The level of measurement refers to the way in which variables are quantified and classified. It is crucial for determining the appropriate statistical analysis for research data. There are four levels of measurement: nominal, ordinal, interval, and ratio.
Each level has specific characteristics and determines which statistical tests are valid.

• Nominal: Categories without a natural order (e.g., gender, race)
• Ordinal: Categories with a natural order, but no uniform scale (e.g., survey responses like 'always,' 'sometimes,' 'never')
• Interval: Numerical scales with equal intervals but no true zero (e.g., temperature)
• Ratio: Numerical scales with a true zero (e.g., income, age)

Understanding these levels helps in choosing the right method for data analysis.

Research Methodology

Research methodology encompasses the systematic approaches and techniques used for collecting and analyzing data in social science. It includes various research designs, sampling methods, and data collection techniques.
Proper research methodology ensures the validity, reliability, and generalizability of research findings.

• Experimental design: Used to assess causality by manipulating independent variables
• Survey research: Useful for gathering descriptive data from large populations
• Case studies: In-depth analysis of single units or small groups
• Ethnography: Detailed study of cultural practices and participants' viewpoints

Choosing the right methodology depends on research questions, hypotheses, and available resources.

Political Science

Political science studies the systems of governance, political activities, political thoughts, and political entities. Research often focuses on understanding the structure, processes, and behaviors within governmental systems.
It involves analysis of policy-making, political behavior, and institutional design.

• Topics include democracy, political ideologies, voter behavior
• Methods include comparative studies, case studies, and statistical modeling
• Common variables: voter turnout, political participation, rights and freedoms

Political science research contributes to knowledge about how political systems affect societal outcomes and individual behaviors.

Public Health

Public health focuses on protecting and improving the health of populations through research, policy-making, and community health initiatives. It addresses health behaviors, disease prevention, health education, and access to healthcare.
Research in public health uses both qualitative and quantitative methods to study health outcomes and determinants.

• Common topics: disease prevalence, health disparities, health policy impacts
• Variables: vaccination rates, mortality rates, access to healthcare
• Methods: surveys, observational studies, randomized controlled trials

By understanding public health research, we can develop interventions and policies that improve community health outcomes.

Experimental Design

Experimental design in social science involves creating controlled conditions to test hypotheses about causal relationships between variables. Researchers manipulate one or more independent variables and measure their effect on dependent variables.
Key components of experimental design include randomization, control groups, and replication.

• Types of designs: randomized controlled trials, quasi-experimental designs
• Benefits: ability to infer causality, control over extraneous variables
• Challenges: ethical considerations, artificial settings

Good experimental design maximizes internal and external validity, ensuring that findings are both accurate and generalizable.

Survey Research

Survey research involves collecting data from a sample of individuals using questionnaires or interviews. It is a common method for gathering information about attitudes, behaviors, and characteristics of large populations.
Surveys can be conducted in person, by phone, mail, or online.

• Types of surveys: cross-sectional, longitudinal
• Advantages: efficient data collection, large sample sizes, flexibility
• Limitations: response biases, question wording effects

Effective survey design requires careful question construction, sampling techniques, and consideration of ethical issues to ensure reliable and valid data.

Social Science Statistics

Social science statistics involve the application of statistical methods to analyze data collected in social research. These methods help researchers understand relationships, test hypotheses, and make informed decisions based on data.
Common statistical techniques include descriptive statistics, inferential statistics, and regression analysis.

• Descriptive statistics: summarize data (e.g., mean, median, mode)
• Inferential statistics: draw conclusions about populations based on samples (e.g., t-tests, ANOVA)
• Regression analysis: examine relationships between variables

Proficiency in social science statistics is essential for accurately interpreting and presenting research findings, ensuring they contribute valuable insights to the field.