Quantitative Research Designs

Quantitative Research Designs Quantitative Research Designs Descriptive

Descriptive  Describe phenomena as they exist. Descriptive studiesDescribe phenomena as they exist. Descriptive studies

generally take raw data and summarize it in a useable form. generally take raw data and summarize it in a useable form.



 Can also be qualitative in nature if the sample size is small andCan also be qualitative in nature if the sample size is small and

data are collected from questionnaires, interviews or data are collected from questionnaires, interviews or observations.

observations. Definition and Purpose Definition and Purpose

Descriptive research designs help provide answers to the questions of Descriptive research designs help provide answers to the questions of who, what, when, where, and how associated with a particular research who, what, when, where, and how associated with a particular research problem; a descriptive study cannot conclusively ascertain answers to problem; a descriptive study cannot conclusively ascertain answers to why. Descriptive research is used to obtain information concerning the why. Descriptive research is used to obtain information concerning the current status of the phenomena and to describe "what exists" with current status of the phenomena and to describe "what exists" with respect to variables or conditions in a situation.

respect to variables or conditions in a situation. What do these studies tell you?

What do these studies tell you? 1.

1. The subject is being The subject is being observed in a observed in a completely natural andcompletely natural and unchanged natural environment. True experiments, whilst giving unchanged natural environment. True experiments, whilst giving analyzable data, often adversely influence the normal behavior analyzable data, often adversely influence the normal behavior of the subject.

of the subject. 2.

2. Descriptive researDescriptive research is och is often used as ften used as a pre-cursor to morea pre-cursor to more quantitatively research designs, the general overview giving quantitatively research designs, the general overview giving some valuable pointers as to what variables are worth testing some valuable pointers as to what variables are worth testing quantitatively.

quantitatively. 3.

3. If the limitations are If the limitations are understood, they can understood, they can be a be a useful tool inuseful tool in developing a more focused study.

developing a more focused study. 4.

4. Descriptive studies can yield Descriptive studies can yield rich data that rich data that lead to lead to importantimportant recommendations.

recommendations. 5.

5. Appoach collects a Appoach collects a large amount large amount of data of data for detailed for detailed analysis.analysis. What these studies don't tell you?

What these studies don't tell you? 1.

1. The results from a The results from a descriptive researcdescriptive research can nh can not be used ot be used toto discover a definitive answer or to disprove a hypothesis.

discover a definitive answer or to disprove a hypothesis. 2.

2. Because Because descriptive designs descriptive designs often often utilize observational utilize observational methodsmethods [as opposed to quantitative methods], the results cannot be [as opposed to quantitative methods], the results cannot be replicated.

replicated. 3.

3. The descriptive function of The descriptive function of research is heavily research is heavily dependent ondependent on instrumentation for measurement and observation.

instrumentation for measurement and observation.

Experimental

Experimental  The art of planning and implementing an experiment in whichThe art of planning and implementing an experiment in which

the research has control over some of the conditions where the the research has control over some of the conditions where the study takes place and control over some aspects of the

study takes place and control over some aspects of the

independent variable(s) (presumed cause or variable used to independent variable(s) (presumed cause or variable used to

predict another variable) predict another variable)

A blueprint of the procedure that enables the researcher to maintain A blueprint of the procedure that enables the researcher to maintain control over all factors that may affect the result of an experiment. In control over all factors that may affect the result of an experiment. In doing this, the researcher attempts to determine or predict what may doing this, the researcher attempts to determine or predict what may occur. Experimental Research is often used where there is time priority occur. Experimental Research is often used where there is time priority in a causal relationship (cause precedes effect), there is consistency in in a causal relationship (cause precedes effect), there is consistency in a causal relationship (a cause will always lead to the same effect), and a causal relationship (a cause will always lead to the same effect), and the magnitude of the correlation is great. The classic experimental the magnitude of the correlation is great. The classic experimental design specifies an experimental group and a control group. The design specifies an experimental group and a control group. The independent variable is administered to the experimental group and not independent variable is administered to the experimental group and not to the control group, and both groups are measured on the same to the control group, and both groups are measured on the same dependent variable. Subsequent experimental designs have used more dependent variable. Subsequent experimental designs have used more groups and more measurements over longer periods. True experiments groups and more measurements over longer periods. True experiments must have control, randomization, and manipulation.

must have control, randomization, and manipulation. What do these studies tell you?

What do these studies tell you? 1.

1. Experimental research allows the researcher to control theExperimental research allows the researcher to control the situation. In so doing, it allows researchers to answer the situation. In so doing, it allows researchers to answer the question, “what causes something to occur?”

question, “what causes something to occur?” 2.

2. Permits the Permits the researcher to researcher to identify cause identify cause and and effect relationshipseffect relationships between variables and to distinguish placebo effects from between variables and to distinguish placebo effects from treatment effects.

treatment effects.

3. Experimental research designs support the ability to limit 3. Experimental research designs support the ability to limit alternative explanations and to infer direct causal relationships alternative explanations and to infer direct causal relationships in the study.

in the study. 4.

4. Approach provides the highest level Approach provides the highest level of evidence for singleof evidence for single studies.

studies.

What these studies don't tell you? What these studies don't tell you?

1.

1. The design The design is artificial, and is artificial, and results may not results may not generalize well togeneralize well to the real world.

the real world. 2.

2. The The artificiaartificial l settings of settings of experiments may experiments may alter subject alter subject behaviorsbehaviors or responses.

or responses. 3.

3. Experimental designs can be Experimental designs can be costly if special equipment orcostly if special equipment or facilities are needed.

facilities are needed.

4. Some research problems cannot be studied using an 4. Some research problems cannot be studied using an

experiment because of ethical or technical reasons. experiment because of ethical or technical reasons. 5.

5. DifficulDifficult t to to apply ethnographic apply ethnographic and and other qualitative other qualitative methods tomethods to experimental designed research studies.

experimental designed research studies.

Quasi-experimental

Quasi-experimental  A form of experimental research. One in which the researcherA form of experimental research. One in which the researcher

cannot control at least one of the three elements of an cannot control at least one of the three elements of an experimental design:

experimental design:





 Intervention (program or practice)Intervention (program or practice) 

 Assignment to experimental and control groupsAssignment to experimental and control groups

Qualitative Research Designs Qualitative Research Designs Historical

Historical  Collection and evaluation of data related to past events that areCollection and evaluation of data related to past events that are

used to describe causes, effects and trends that may explain used to describe causes, effects and trends that may explain present or future events. Data are often archival.

present or future events. Data are often archival.



 Data includes interviews.Data includes interviews.

Definition and Purpose Definition and Purpose

The purpose of a historical research design is to collect, verify, and The purpose of a historical research design is to collect, verify, and synthesize evidence from the past to establish facts that defend or synthesize evidence from the past to establish facts that defend or refute your hypothesis. It uses secondary sources and a variety of refute your hypothesis. It uses secondary sources and a variety of primary documentary evidence, such as, logs, diaries, official records, primary documentary evidence, such as, logs, diaries, official records, reports, archives, and non-textual information [maps, pictures, audio reports, archives, and non-textual information [maps, pictures, audio and visual recordings]. The limitation is that the sources must be both and visual recordings]. The limitation is that the sources must be both authentic and valid.

authentic and valid.

What do these studies tell you? What do these studies tell you?

1. The historical research design is unobtrusive; the act of 1. The historical research design is unobtrusive; the act of

research does not affect the results of the study. research does not affect the results of the study. 2.

2. The The historichistorical al approach is approach is well suited well suited for trend for trend analysis.analysis. 3.

3. Historical records can add Historical records can add important contextual backgroundimportant contextual background required to more fully understand and interpret a research required to more fully understand and interpret a research problem.

problem. 4.

4. There is There is no possibility of no possibility of researcherresearcher-subject interaction that-subject interaction that could affect the findings.

could affect the findings. 5.

5. HistoricaHistorical sources l sources can be can be used over used over and over and over to study to study differentdifferent research problems or to replicate a previous study.

research problems or to replicate a previous study. What these studies don't tell you?

What these studies don't tell you? 1.

1. The ability The ability to fulfill the to fulfill the aims of yoaims of your research ur research are directare directly relatedly related to the amount and quality of documentation available to to the amount and quality of documentation available to understand the research problem.

understand the research problem. 2.

2. Since historical research relies Since historical research relies on data on data from the from the past, there past, there isis no way to manipulate it to control for contemporary contexts. no way to manipulate it to control for contemporary contexts. 3.

3. Interpreting historical sources Interpreting historical sources can can be be very very time consuming.time consuming. 4. The sources of historical materials must be archived 4. The sources of historical materials must be archived

consistentally to ensure access. consistentally to ensure access. 5.

5. Original authors bring Original authors bring their own their own perspectives and biases perspectives and biases to theto the interpretation of past events and these biases are more difficult interpretation of past events and these biases are more difficult to ascertain in historical resources.

to ascertain in historical resources. 6.

6. Due to Due to the lack of the lack of control over external variables, historicalcontrol over external variables, historical research is very weak with regard to the demands of internal research is very weak with regard to the demands of internal validity.

validity. 7.

fully address a research problem is available for interpretation, fully address a research problem is available for interpretation, therefore, gaps need to be acknowledged.

therefore, gaps need to be acknowledged.

Ethnographic

Ethnographic  The collection of extensive narrative data over an extendedThe collection of extensive narrative data over an extended

period of time in natural settings to gain insights about other period of time in natural settings to gain insights about other types of research.

types of research.



 Data are collected through observations at particular points ofData are collected through observations at particular points of

time over a sustained period. time over a sustained period.



 Data include observations, records and interpretations of whatData include observations, records and interpretations of what

is seen. is seen.

Case Studies

Case Studies  An in-depth study of an individual group, institution, organizationAn in-depth study of an individual group, institution, organization

or program. or program.



 Data include interviews, field notes of observations, archivalData include interviews, field notes of observations, archival

data and biographical data. data and biographical data. Definition and Purpose

Definition and Purpose

A case study is an in-depth study of a particular research problem A case study is an in-depth study of a particular research problem rather than a sweeping statistical survey. It is often used to narrow rather than a sweeping statistical survey. It is often used to narrow down a very broad field of research into one or a few easily down a very broad field of research into one or a few easily researchable examples. The case study research design is also useful researchable examples. The case study research design is also useful for testing whether a specific theory and model actually applies to for testing whether a specific theory and model actually applies to phenomena in the real world. It is a useful design when not much is phenomena in the real world. It is a useful design when not much is known about a phenomenon.

known about a phenomenon. What do these studies tell you? What do these studies tell you?

1.

1. Approach excels at bringing us to an undeApproach excels at bringing us to an understanding of arstanding of a complex issue through detailed contextual analysis of a limited complex issue through detailed contextual analysis of a limited number of events or conditions and their relationships.

number of events or conditions and their relationships. 2.

2. A researcher using a A researcher using a case study design can case study design can apply a vaiety apply a vaiety ofof methodologies and rely on a variety of sources to investigate a methodologies and rely on a variety of sources to investigate a research problem.

research problem. 3.

3. Design can extend experience or add strength to what Design can extend experience or add strength to what isis already known through previous research.

already known through previous research. 4.

4. Social scienSocial scientists, in particulatists, in particular, make wide use or, make wide use of this researchf this research design to examine contemporary real-life situations and provide design to examine contemporary real-life situations and provide the basis for the application of concepts and theories and the basis for the application of concepts and theories and extension of methods.

extension of methods. 5.

5. The design The design can provide can provide detailed descriptions of specific anddetailed descriptions of specific and rare cases.

rare cases.

What these studies don't tell you? What these studies don't tell you?

1. A single or small number of cases offers little basis for 1. A single or small number of cases offers little basis for establishing reliability or to generalize the findings to a wider establishing reliability or to generalize the findings to a wider population of people, places, or things.

2. The intense exposure to study of the case may bias a 2. The intense exposure to study of the case may bias a

researcher's interpretation of the findings. researcher's interpretation of the findings. 3.

3. Design does not Design does not facilitatfacilitate assessment of cause e assessment of cause and effectand effect relationships.

relationships. 4.

4. Vital information may be missing, making the Vital information may be missing, making the case hard tocase hard to interpret.

interpret. 5.

5. The case may The case may not be not be representatirepresentative or ve or typical of the largertypical of the larger problem being investigated.

problem being investigated. 6.

6. If the criteIf the criteria for selectria for selecting a case ing a case is becausis because it represents a e it represents a veryvery unusual or unique phenomenon or problem for study, then your unusual or unique phenomenon or problem for study, then your intepretation of the findings can only apply to that particular intepretation of the findings can only apply to that particular case.

case.

Phenomology