1. Describe the kinds of relationships that lend themselves to study with experimental or quasi-experimental designs. Provide an example of each one.

When we discuss cross-sectional designs, they tend to portray a weaker internal validity compared to the experimental designs. Besides, with cross-sectional designs, researchers have the notion of depending on techniques of data analysis as an approach for control. Regarding the quasi-experimental designs, researchers can use the population to choose samples randomly; however, it is not possible to assign individuals randomly to the comparison group. The superiority of quasi-experimental designs is more compared to cross-sectional designs since they entail studying more than one sample of a population (Frankfort-Nachmias & Nachmias, 2015). Moreover, the study takes place over an extended time.

  1. Identify and discuss the four key differences between stimulus-response relationships and property-disposition relationships?

Stimulus-response relationships are types of relationships that feature an independent variable that the researcher can manipulate. Conversely, with property-disposition relationships, the association is between characteristics of a person and corresponding attitude of inclination (Frankfort-Nachmias & Nachmias, 2015). For instance, personal properties include heritage, age, and gender while personal disposition includes attitude and values. The following four ways show the difference between stimulus response and property disposition.

First, regarding time interval, the stimulus-response relationship has a relatively short time interval. The association exhibits a short time interval regarding the experience the independent variable is introduced and the reaction to it. For instance, a response to an advertising campaign (Frankfort-Nachmias & Nachmias, 2015). With property-disposition, the researcher can extend the time interval over an extended period.

Second, regarding the degree of specificity, the researcher can easily separate and identify the independent variable in a stimulus response. Moreover, the researcher can delineate its effect. Conversely, the property-disposition relationship is more general; therefore, it is hard for researchers to determine pertinent causes and try to manipulate the relationship.

Third, regarding the nature of comparison group, in a stimulus-response relationship, it is possible for the researcher to compare two similar groups (Frankfort-Nachmias & Nachmias, 2015). The two groups include the experimental groups and the control group. Moreover, the researcher can compare same groups before and after exposing them to stimulus.

The last difference is the time sequence of events. The stimulus-response relationship shows a relatively clear direction of causation. This is possible in a situation when the researcher can make a before and after comparison using the existing research design.

  1. Develop a quasi-experimental design to study the effect of introductory social science courses on attitudes toward cultural diversity. Be sure to explain your logic and the advantages and disadvantages of this design.

Quasi-experimental designs encompass studying more than one sample over time. With these designs, researchers select samples randomly from the given population (Frankfort-Nachmias & Nachmias, 2015). However, regarding the internal validity, quasi-experimental designs have a lower internal validity compared to controlled experiments. Besides, as a method of control, the designs depend on techniques of data analysis.

  1. Discuss the logic of cross-sectional designs and how (e.g., under what types of research conditions) this design fits into social science research.

The field of social sciences widely depends on using cross-sectional designs. The designs are useful when conducting survey research. With this design, the role of the researcher is to select a random sample of the population and ask questions regarding their background, attitude, opinions and past experiences. Other studies focus on determining the causal relationship between variables, but with cross-sectional studies, researchers focus on providing a description of the relationship between variables (Frankfort-Nachmias & Nachmias, 2015).

  1. Identify and discuss the major types of quasi-experimental designs?

The first type is time series design. It refers to the designs that measure the dependent variable severally prior to and after the occurrence of the quasi-independent variable. Besides, it entails pre-testing and post-testing of a single group of elements at a varying interval. Second, with non-equivalent control group design, the researcher selects a group of respondents who are similar to the group that receives the quasi-independent variable (Frankfort-Nachmias & Nachmias, 2015). The idea is to compare the treated group to the comparison group. Third, the regression-discontinuity design is useful for researchers when establishing the effectiveness of a program of treatment. The researcher assigns participants to a program basing on a cutoff score on a pre-test.

  1. What are pre-experimental designs? How and why are pre-experimental designs used in social science research?

It refers to designs that follow fundamental experimental sequence; however, they do not include a control group. Besides, the researcher studies a single group but does not make a comparison between an equivalent non-treatment groups (Frankfort-Nachmias & Nachmias, 2015). Pre-experimental designs are useful in controversial issues when it is hard for the researcher to implement a quasi-experimental design. For instance, a case study that involves observing a single group that relates to the phenomenon that caused the change.

  1. Discuss the limitations of pre-experimental designs.

First the researcher cannot conduct successful experimental manipulations with pre-experimental designs. Similarly, with pre-experimental designs, the researcher cannot assign cases randomly to both experimental and control groups. Second, participants in this designs are not selected randomly from the population (Frankfort-Nachmias & Nachmias, 2015). Also, the researcher does not use multivariate statistics as an alternative to experimental control.

  1. Describe and give one or more examples of a one-shot case study.

It refers to the case study that encompasses a researcher observing a single group that relates to the phenomenon that caused the change (Frankfort-Nachmias & Nachmias, 2015). Examples of a one-shot case study include observing the political system of a nation after they concluded the general elections. Also, one can observe the community after a successful urban renewal program. The researcher can observe a learning institution after it has employed innovative teaching methods.

  1. Compare and contrast research designs in terms of the dilemma of internal versus external validity.

When using experiments, scientists can increase external validity by providing a clear definition of the population under investigation and use the population to draw sampling units as a result of the probability sample design (Frankfort-Nachmias & Nachmias, 2015). With cross-sectional studies and quasi-experiments, scientists can improve the internal validity to a greater extent by involving supplemental evidence to control rival hypotheses.



Frankfort-Nachmias, C., & Nachmias, D. (2015). Research methods in the social sciences (8th ed.). New York, NY: Worth Publishers, a Macmillan Education Company.