{"id":69,"date":"2017-11-16T17:40:24","date_gmt":"2017-11-16T17:40:24","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/chapter\/7-1-overview-of-nonexperimental-research\/"},"modified":"2017-11-16T17:40:24","modified_gmt":"2017-11-16T17:40:24","slug":"7-1-overview-of-nonexperimental-research","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/chapter\/7-1-overview-of-nonexperimental-research\/","title":{"raw":"7.1 Overview of Nonexperimental Research","rendered":"7.1 Overview of Nonexperimental Research"},"content":{"raw":"<div class=\"bcc-box bcc-highlight\" id=\"price_1.0-ch07_s01_n01\">\n        <h3 class=\"title\">Learning Objectives<\/h3>\n        <ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_l01\"><li>Define nonexperimental research, distinguish it clearly from experimental research, and give several examples.<\/li>\n            <li>Explain when a researcher might choose to conduct nonexperimental research as opposed to experimental research.<\/li>\n        <\/ol><\/div>\n    <div class=\"section\" id=\"price_1.0-ch07_s01_s01\">\n        <h2 class=\"title editable block\">What Is Nonexperimental Research?<\/h2>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s01_p01\"><span class=\"margin_term\"><b>Nonexperimental research<\/b><\/span> is research that lacks the manipulation of an independent variable, random assignment of participants to conditions or orders of conditions, or both.<\/p>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s01_p02\">In a sense, it is unfair to define this large and diverse set of approaches collectively by what they are <em class=\"emphasis\">not<\/em>. But doing so reflects the fact that most researchers in psychology consider the distinction between experimental and nonexperimental research to be an extremely important one. This is because while experimental research can provide strong evidence that changes in an independent variable cause differences in a dependent variable, nonexperimental research generally cannot. As we will see, however, this does not mean that nonexperimental research is less important than experimental research or inferior to it in any general sense.<\/p>\n    <\/div>\n    <div class=\"section\" id=\"price_1.0-ch07_s01_s02\">\n        <h2 class=\"title editable block\">When to Use Nonexperimental Research<\/h2>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s02_p01\">As we saw in <a class=\"xref\" href=\"..\/6-1-experiment-basics\/#price_1.0-ch06\">Chapter 6 \"Experimental Research\"<\/a>, experimental research is appropriate when the researcher has a specific research question or hypothesis about a causal relationship between two variables\u2014and it is possible, feasible, and ethical to manipulate the independent variable and randomly assign participants to conditions or to orders of conditions. It stands to reason, therefore, that nonexperimental research is appropriate\u2014even necessary\u2014when these conditions are not met. There are many ways in which this can be the case.<\/p>\n        <ul class=\"itemizedlist editable block\" id=\"price_1.0-ch07_s01_s02_l01\"><li>The research question or hypothesis can be about a single variable rather than a statistical relationship between two variables (e.g., How accurate are people\u2019s first impressions?).<\/li>\n            <li>The research question can be about a noncausal statistical relationship between variables (e.g., Is there a correlation between verbal intelligence and mathematical intelligence?).<\/li>\n            <li>The research question can be about a causal relationship, but the independent variable cannot be manipulated or participants cannot be randomly assigned to conditions or orders of conditions (e.g., Does damage to a person\u2019s hippocampus impair the formation of long-term memory traces?).<\/li>\n            <li>The research question can be broad and exploratory, or it can be about what it is like to have a particular experience (e.g., What is it like to be a working mother diagnosed with depression?).<\/li>\n        <\/ul><p class=\"para editable block\" id=\"price_1.0-ch07_s01_s02_p02\">Again, the choice between the experimental and nonexperimental approaches is generally dictated by the nature of the research question. If it is about a causal relationship and involves an independent variable that can be manipulated, the experimental approach is typically preferred. Otherwise, the nonexperimental approach is preferred. But the two approaches can also be used to address the same research question in complementary ways. For example, nonexperimental studies establishing that there is a relationship between watching violent television and aggressive behavior have been complemented by experimental studies confirming that the relationship is a causal one (Bushman &amp; Huesmann, 2001). Similarly, after his original study, Milgram conducted experiments to explore the factors that affect obedience. He manipulated several independent variables, such as the distance between the experimenter and the participant, the participant and the confederate, and the location of the study (Milgram, 1974).<\/p>\n    <\/div>\n    <div class=\"section\" id=\"price_1.0-ch07_s01_s03\">\n        <h2 class=\"title editable block\">Types of Nonexperimental Research<\/h2>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p01\">Nonexperimental research falls into three broad categories: single-variable research, correlational and quasi-experimental research, and qualitative research. First, research can be nonexperimental because it focuses on a single variable rather than a statistical relationship between two variables. Although there is no widely shared term for this kind of research, we will call it <span class=\"margin_term\"><b>single-variable research<\/b><\/span>. Milgram\u2019s original obedience study was nonexperimental in this way. He was primarily interested in one variable\u2014the extent to which participants obeyed the researcher when he told them to shock the confederate\u2014and he observed all participants performing the same task under the same conditions. The study by Loftus and Pickrell described at the beginning of this chapter is also a good example of single-variable research. The variable was whether participants \u201cremembered\u201d having experienced mildly traumatic childhood events (e.g., getting lost in a shopping mall) that they had not actually experienced but that the research asked them about repeatedly. In this particular study, nearly a third of the participants \u201cremembered\u201d at least one event. (As with Milgram\u2019s original study, this study inspired several later experiments on the factors that affect false memories.)<\/p>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p02\">As these examples make clear, single-variable research can answer interesting and important questions. What it cannot do, however, is answer questions about statistical relationships between variables. This is a point that beginning researchers sometimes miss. Imagine, for example, a group of research methods students interested in the relationship between children\u2019s being the victim of bullying and the children\u2019s self-esteem. The first thing that is likely to occur to these researchers is to obtain a sample of middle-school students who have been bullied and then to measure their self-esteem. But this would be a single-variable study with self-esteem as the only variable. Although it would tell the researchers something about the self-esteem of children who have been bullied, it would not tell them what they really want to know, which is how the self-esteem of children who have been bullied <em class=\"emphasis\">compares<\/em> with the self-esteem of children who have not. Is it lower? Is it the same? Could it even be higher? To answer this question, their sample would also have to include middle-school students who have not been bullied.<\/p>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p04\">Research can also be nonexperimental because it focuses on a statistical relationship between two variables but does not include the manipulation of an independent variable, random assignment of participants to conditions or orders of conditions, or both. This kind of research takes two basic forms: correlational research and quasi-experimental research. In <span class=\"margin_term\"><b>correlational research<\/b><\/span>, the researcher measures the two variables of interest with little or no attempt to control extraneous variables and then assesses the relationship between them. A research methods student who finds out whether each of several middle-school students has been bullied and then measures each student\u2019s self-esteem is conducting correlational research. In <span class=\"margin_term\"><b>quasi-experimental research<\/b><\/span>, the researcher manipulates an independent variable but does not randomly assign participants to conditions or orders of conditions. For example, a researcher might start an antibullying program (a kind of treatment) at one school and compare the incidence of bullying at that school with the incidence at a similar school that has no antibullying program.<\/p>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p05\">The final way in which research can be nonexperimental is that it can be qualitative. The types of research we have discussed so far are all quantitative, referring to the fact that the data consist of numbers that are analyzed using statistical techniques. In <span class=\"margin_term\"><b>qualitative research<\/b><\/span>, the data are usually nonnumerical and are analyzed using nonstatistical techniques. Rosenhan\u2019s study of the experience of people in a psychiatric ward was primarily qualitative. The data were the notes taken by the \u201cpseudopatients\u201d\u2014the people pretending to have heard voices\u2014along with their hospital records. Rosenhan\u2019s analysis consists mainly of a written description of the experiences of the pseudopatients, supported by several concrete examples. To illustrate the hospital staff\u2019s tendency to \u201cdepersonalize\u201d their patients, he noted, \u201cUpon being admitted, I and other pseudopatients took the initial physical examinations in a semipublic room, where staff members went about their own business as if we were not there\u201d (Rosenhan, 1973, p. 256).<\/p>\n    <\/div>\n    <div class=\"section\" id=\"price_1.0-ch07_s01_s04\">\n        <h2 class=\"title editable block\">Internal Validity Revisited<\/h2>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s04_p01\">Recall that internal validity is the extent to which the design of a study supports the conclusion that changes in the independent variable caused any observed differences in the dependent variable. <a class=\"xref\" href=\"#price_1.0-ch07_s01_s04_f01\">Figure 7.1<\/a> shows how experimental, quasi-experimental, and correlational research vary in terms of internal validity. Experimental research tends to be highest because it addresses the directionality and third-variable problems through manipulation and the control of extraneous variables through random assignment. If the average score on the dependent variable in an experiment differs across conditions, it is quite likely that the independent variable is responsible for that difference. Correlational research is lowest because it fails to address either problem. If the average score on the dependent variable differs across levels of the independent variable, it <em class=\"emphasis\">could<\/em> be that the independent variable is responsible, but there are other interpretations. In some situations, the direction of causality could be reversed. In others, there could be a third variable that is causing differences in both the independent and dependent variables. Quasi-experimental research is in the middle because the manipulation of the independent variable addresses some problems, but the lack of random assignment and experimental control fails to address others. Imagine, for example, that a researcher finds two similar schools, starts an antibullying program in one, and then finds fewer bullying incidents in that \u201ctreatment school\u201d than in the \u201ccontrol school.\u201d There is no directionality problem because clearly the number of bullying incidents did not determine which school got the program. However, the lack of random assignment of children to schools could still mean that students in the treatment school differed from students in the control school in some other way that could explain the difference in bullying.<\/p>\n        <div style=\"text-align: center; font-size: .8em;\" id=\"price_1.0-ch07_s01_s04_f01\">\n            <p class=\"title\"><span class=\"title-prefix\">Figure 7.1<\/span> <\/p>\n            <a href=\"\/psychologyresearchmethods\/wp-content\/uploads\/sites\/171\/2015\/07\/d5de1bd14f8973e88e5869d400a1bce5.jpg\"><img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/2714\/2017\/11\/16174023\/d5de1bd14f8973e88e5869d400a1bce5.jpg\" alt=\"Experiments are generally high in internal validity, quasi-experiments lower, and correlational studies lower still\" style=\"max-width: 497px;\"\/><\/a><p class=\"para\">Experiments are generally high in internal validity, quasi-experiments lower, and correlational studies lower still.<\/p>\n        <\/div>\n        <p class=\"para editable block\" id=\"price_1.0-ch07_s01_s04_p02\">Notice also in <a class=\"xref\" href=\"#price_1.0-ch07_s01_s04_f01\">Figure 7.1<\/a> that there is some overlap in the internal validity of experiments, quasi-experiments, and correlational studies. For example, a poorly designed experiment that includes many confounding variables can be lower in internal validity than a well designed quasi-experiment with no obvious confounding variables.<\/p>\n        <div class=\"bcc-box bcc-success\" id=\"price_1.0-ch07_s01_s04_n01\">\n            <h3 class=\"title\">Key Takeaways<\/h3>\n            <ul class=\"itemizedlist\" id=\"price_1.0-ch07_s01_s04_l01\"><li>Nonexperimental research is research that lacks the manipulation of an independent variable, control of extraneous variables through random assignment, or both.<\/li>\n                <li>There are three broad types of nonexperimental research. Single-variable research focuses on a single variable rather than a relationship between variables. Correlational and quasi-experimental research focus on a statistical relationship but lack manipulation or random assignment. Qualitative research focuses on broader research questions, typically involves collecting large amounts of data from a small number of participants, and analyzes the data nonstatistically.<\/li>\n                <li>In general, experimental research is high in internal validity, correlational research is low in internal validity, and quasi-experimental research is in between.<\/li>\n            <\/ul><\/div>\n        <div class=\"bcc-box bcc-info\" id=\"price_1.0-ch07_s01_s04_n02\">\n            <h3 class=\"title\">Exercise<\/h3>\n            <ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_s04_l02\"><li>\n                    <p class=\"para\">Discussion: For each of the following studies, decide which type of research design it is and explain why.<\/p>\n                    <ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_s04_l03\"><li>A researcher conducts detailed interviews with unmarried teenage fathers to learn about how they feel and what they think about their role as fathers and summarizes their feelings in a written narrative.<\/li>\n                        <li>A researcher measures the impulsivity of a large sample of drivers and looks at the statistical relationship between this variable and the number of traffic tickets the drivers have received.<\/li>\n                        <li>A researcher randomly assigns patients with low back pain either to a treatment involving hypnosis or to a treatment involving exercise. She then measures their level of low back pain after 3 months.<\/li>\n                        <li>A college instructor gives weekly quizzes to students in one section of his course but no weekly quizzes to students in another section to see whether this has an effect on their test performance.<\/li>\n                    <\/ol><\/li>\n            <\/ol><\/div>\n    <\/div>\n\n\n<h2>References<\/h2>\n\nBushman, B. J., &amp; Huesmann, L. R. (2001). Effects of televised violence on aggression. In D. Singer &amp; J. Singer (Eds.), <em class=\"emphasis\">Handbook of children and the media<\/em> (pp. 223\u2013254). Thousand Oaks, CA: Sage.\n<br\/><br\/>\nMilgram, S. (1974). <em class=\"emphasis\">Obedience to authority: An experimental view<\/em>. New York, NY: Harper &amp; Row.\n<br\/><br\/>\nRosenhan, D. L. (1973). On being sane in insane places. <em class=\"emphasis\">Science, 179<\/em>, 250\u2013258.","rendered":"<div class=\"bcc-box bcc-highlight\" id=\"price_1.0-ch07_s01_n01\">\n<h3 class=\"title\">Learning Objectives<\/h3>\n<ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_l01\">\n<li>Define nonexperimental research, distinguish it clearly from experimental research, and give several examples.<\/li>\n<li>Explain when a researcher might choose to conduct nonexperimental research as opposed to experimental research.<\/li>\n<\/ol>\n<\/div>\n<div class=\"section\" id=\"price_1.0-ch07_s01_s01\">\n<h2 class=\"title editable block\">What Is Nonexperimental Research?<\/h2>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s01_p01\"><span class=\"margin_term\"><b>Nonexperimental research<\/b><\/span> is research that lacks the manipulation of an independent variable, random assignment of participants to conditions or orders of conditions, or both.<\/p>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s01_p02\">In a sense, it is unfair to define this large and diverse set of approaches collectively by what they are <em class=\"emphasis\">not<\/em>. But doing so reflects the fact that most researchers in psychology consider the distinction between experimental and nonexperimental research to be an extremely important one. This is because while experimental research can provide strong evidence that changes in an independent variable cause differences in a dependent variable, nonexperimental research generally cannot. As we will see, however, this does not mean that nonexperimental research is less important than experimental research or inferior to it in any general sense.<\/p>\n<\/p><\/div>\n<div class=\"section\" id=\"price_1.0-ch07_s01_s02\">\n<h2 class=\"title editable block\">When to Use Nonexperimental Research<\/h2>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s02_p01\">As we saw in <a class=\"xref\" href=\"..\/6-1-experiment-basics\/#price_1.0-ch06\">Chapter 6 &#8220;Experimental Research&#8221;<\/a>, experimental research is appropriate when the researcher has a specific research question or hypothesis about a causal relationship between two variables\u2014and it is possible, feasible, and ethical to manipulate the independent variable and randomly assign participants to conditions or to orders of conditions. It stands to reason, therefore, that nonexperimental research is appropriate\u2014even necessary\u2014when these conditions are not met. There are many ways in which this can be the case.<\/p>\n<ul class=\"itemizedlist editable block\" id=\"price_1.0-ch07_s01_s02_l01\">\n<li>The research question or hypothesis can be about a single variable rather than a statistical relationship between two variables (e.g., How accurate are people\u2019s first impressions?).<\/li>\n<li>The research question can be about a noncausal statistical relationship between variables (e.g., Is there a correlation between verbal intelligence and mathematical intelligence?).<\/li>\n<li>The research question can be about a causal relationship, but the independent variable cannot be manipulated or participants cannot be randomly assigned to conditions or orders of conditions (e.g., Does damage to a person\u2019s hippocampus impair the formation of long-term memory traces?).<\/li>\n<li>The research question can be broad and exploratory, or it can be about what it is like to have a particular experience (e.g., What is it like to be a working mother diagnosed with depression?).<\/li>\n<\/ul>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s02_p02\">Again, the choice between the experimental and nonexperimental approaches is generally dictated by the nature of the research question. If it is about a causal relationship and involves an independent variable that can be manipulated, the experimental approach is typically preferred. Otherwise, the nonexperimental approach is preferred. But the two approaches can also be used to address the same research question in complementary ways. For example, nonexperimental studies establishing that there is a relationship between watching violent television and aggressive behavior have been complemented by experimental studies confirming that the relationship is a causal one (Bushman &amp; Huesmann, 2001). Similarly, after his original study, Milgram conducted experiments to explore the factors that affect obedience. He manipulated several independent variables, such as the distance between the experimenter and the participant, the participant and the confederate, and the location of the study (Milgram, 1974).<\/p>\n<\/p><\/div>\n<div class=\"section\" id=\"price_1.0-ch07_s01_s03\">\n<h2 class=\"title editable block\">Types of Nonexperimental Research<\/h2>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p01\">Nonexperimental research falls into three broad categories: single-variable research, correlational and quasi-experimental research, and qualitative research. First, research can be nonexperimental because it focuses on a single variable rather than a statistical relationship between two variables. Although there is no widely shared term for this kind of research, we will call it <span class=\"margin_term\"><b>single-variable research<\/b><\/span>. Milgram\u2019s original obedience study was nonexperimental in this way. He was primarily interested in one variable\u2014the extent to which participants obeyed the researcher when he told them to shock the confederate\u2014and he observed all participants performing the same task under the same conditions. The study by Loftus and Pickrell described at the beginning of this chapter is also a good example of single-variable research. The variable was whether participants \u201cremembered\u201d having experienced mildly traumatic childhood events (e.g., getting lost in a shopping mall) that they had not actually experienced but that the research asked them about repeatedly. In this particular study, nearly a third of the participants \u201cremembered\u201d at least one event. (As with Milgram\u2019s original study, this study inspired several later experiments on the factors that affect false memories.)<\/p>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p02\">As these examples make clear, single-variable research can answer interesting and important questions. What it cannot do, however, is answer questions about statistical relationships between variables. This is a point that beginning researchers sometimes miss. Imagine, for example, a group of research methods students interested in the relationship between children\u2019s being the victim of bullying and the children\u2019s self-esteem. The first thing that is likely to occur to these researchers is to obtain a sample of middle-school students who have been bullied and then to measure their self-esteem. But this would be a single-variable study with self-esteem as the only variable. Although it would tell the researchers something about the self-esteem of children who have been bullied, it would not tell them what they really want to know, which is how the self-esteem of children who have been bullied <em class=\"emphasis\">compares<\/em> with the self-esteem of children who have not. Is it lower? Is it the same? Could it even be higher? To answer this question, their sample would also have to include middle-school students who have not been bullied.<\/p>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p04\">Research can also be nonexperimental because it focuses on a statistical relationship between two variables but does not include the manipulation of an independent variable, random assignment of participants to conditions or orders of conditions, or both. This kind of research takes two basic forms: correlational research and quasi-experimental research. In <span class=\"margin_term\"><b>correlational research<\/b><\/span>, the researcher measures the two variables of interest with little or no attempt to control extraneous variables and then assesses the relationship between them. A research methods student who finds out whether each of several middle-school students has been bullied and then measures each student\u2019s self-esteem is conducting correlational research. In <span class=\"margin_term\"><b>quasi-experimental research<\/b><\/span>, the researcher manipulates an independent variable but does not randomly assign participants to conditions or orders of conditions. For example, a researcher might start an antibullying program (a kind of treatment) at one school and compare the incidence of bullying at that school with the incidence at a similar school that has no antibullying program.<\/p>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s03_p05\">The final way in which research can be nonexperimental is that it can be qualitative. The types of research we have discussed so far are all quantitative, referring to the fact that the data consist of numbers that are analyzed using statistical techniques. In <span class=\"margin_term\"><b>qualitative research<\/b><\/span>, the data are usually nonnumerical and are analyzed using nonstatistical techniques. Rosenhan\u2019s study of the experience of people in a psychiatric ward was primarily qualitative. The data were the notes taken by the \u201cpseudopatients\u201d\u2014the people pretending to have heard voices\u2014along with their hospital records. Rosenhan\u2019s analysis consists mainly of a written description of the experiences of the pseudopatients, supported by several concrete examples. To illustrate the hospital staff\u2019s tendency to \u201cdepersonalize\u201d their patients, he noted, \u201cUpon being admitted, I and other pseudopatients took the initial physical examinations in a semipublic room, where staff members went about their own business as if we were not there\u201d (Rosenhan, 1973, p. 256).<\/p>\n<\/p><\/div>\n<div class=\"section\" id=\"price_1.0-ch07_s01_s04\">\n<h2 class=\"title editable block\">Internal Validity Revisited<\/h2>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s04_p01\">Recall that internal validity is the extent to which the design of a study supports the conclusion that changes in the independent variable caused any observed differences in the dependent variable. <a class=\"xref\" href=\"#price_1.0-ch07_s01_s04_f01\">Figure 7.1<\/a> shows how experimental, quasi-experimental, and correlational research vary in terms of internal validity. Experimental research tends to be highest because it addresses the directionality and third-variable problems through manipulation and the control of extraneous variables through random assignment. If the average score on the dependent variable in an experiment differs across conditions, it is quite likely that the independent variable is responsible for that difference. Correlational research is lowest because it fails to address either problem. If the average score on the dependent variable differs across levels of the independent variable, it <em class=\"emphasis\">could<\/em> be that the independent variable is responsible, but there are other interpretations. In some situations, the direction of causality could be reversed. In others, there could be a third variable that is causing differences in both the independent and dependent variables. Quasi-experimental research is in the middle because the manipulation of the independent variable addresses some problems, but the lack of random assignment and experimental control fails to address others. Imagine, for example, that a researcher finds two similar schools, starts an antibullying program in one, and then finds fewer bullying incidents in that \u201ctreatment school\u201d than in the \u201ccontrol school.\u201d There is no directionality problem because clearly the number of bullying incidents did not determine which school got the program. However, the lack of random assignment of children to schools could still mean that students in the treatment school differed from students in the control school in some other way that could explain the difference in bullying.<\/p>\n<div style=\"text-align: center; font-size: .8em;\" id=\"price_1.0-ch07_s01_s04_f01\">\n<p class=\"title\"><span class=\"title-prefix\">Figure 7.1<\/span> <\/p>\n<p>            <a href=\"\/psychologyresearchmethods\/wp-content\/uploads\/sites\/171\/2015\/07\/d5de1bd14f8973e88e5869d400a1bce5.jpg\"><img decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/2714\/2017\/11\/16174023\/d5de1bd14f8973e88e5869d400a1bce5.jpg\" alt=\"Experiments are generally high in internal validity, quasi-experiments lower, and correlational studies lower still\" style=\"max-width: 497px;\" \/><\/a><\/p>\n<p class=\"para\">Experiments are generally high in internal validity, quasi-experiments lower, and correlational studies lower still.<\/p>\n<\/p><\/div>\n<p class=\"para editable block\" id=\"price_1.0-ch07_s01_s04_p02\">Notice also in <a class=\"xref\" href=\"#price_1.0-ch07_s01_s04_f01\">Figure 7.1<\/a> that there is some overlap in the internal validity of experiments, quasi-experiments, and correlational studies. For example, a poorly designed experiment that includes many confounding variables can be lower in internal validity than a well designed quasi-experiment with no obvious confounding variables.<\/p>\n<div class=\"bcc-box bcc-success\" id=\"price_1.0-ch07_s01_s04_n01\">\n<h3 class=\"title\">Key Takeaways<\/h3>\n<ul class=\"itemizedlist\" id=\"price_1.0-ch07_s01_s04_l01\">\n<li>Nonexperimental research is research that lacks the manipulation of an independent variable, control of extraneous variables through random assignment, or both.<\/li>\n<li>There are three broad types of nonexperimental research. Single-variable research focuses on a single variable rather than a relationship between variables. Correlational and quasi-experimental research focus on a statistical relationship but lack manipulation or random assignment. Qualitative research focuses on broader research questions, typically involves collecting large amounts of data from a small number of participants, and analyzes the data nonstatistically.<\/li>\n<li>In general, experimental research is high in internal validity, correlational research is low in internal validity, and quasi-experimental research is in between.<\/li>\n<\/ul>\n<\/div>\n<div class=\"bcc-box bcc-info\" id=\"price_1.0-ch07_s01_s04_n02\">\n<h3 class=\"title\">Exercise<\/h3>\n<ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_s04_l02\">\n<li>\n<p class=\"para\">Discussion: For each of the following studies, decide which type of research design it is and explain why.<\/p>\n<ol class=\"orderedlist\" id=\"price_1.0-ch07_s01_s04_l03\">\n<li>A researcher conducts detailed interviews with unmarried teenage fathers to learn about how they feel and what they think about their role as fathers and summarizes their feelings in a written narrative.<\/li>\n<li>A researcher measures the impulsivity of a large sample of drivers and looks at the statistical relationship between this variable and the number of traffic tickets the drivers have received.<\/li>\n<li>A researcher randomly assigns patients with low back pain either to a treatment involving hypnosis or to a treatment involving exercise. She then measures their level of low back pain after 3 months.<\/li>\n<li>A college instructor gives weekly quizzes to students in one section of his course but no weekly quizzes to students in another section to see whether this has an effect on their test performance.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<\/div><\/div>\n<h2>References<\/h2>\n<p>Bushman, B. J., &amp; Huesmann, L. R. (2001). Effects of televised violence on aggression. In D. Singer &amp; J. Singer (Eds.), <em class=\"emphasis\">Handbook of children and the media<\/em> (pp. 223\u2013254). Thousand Oaks, CA: Sage.<\/p>\n<p>Milgram, S. (1974). <em class=\"emphasis\">Obedience to authority: An experimental view<\/em>. New York, NY: Harper &amp; Row.<\/p>\n<p>Rosenhan, D. L. (1973). On being sane in insane places. <em class=\"emphasis\">Science, 179<\/em>, 250\u2013258.<\/p>\n\n\t\t\t <section class=\"citations-section\" role=\"contentinfo\">\n\t\t\t <h3>Candela Citations<\/h3>\n\t\t\t\t\t <div>\n\t\t\t\t\t\t <div id=\"citation-list-69\">\n\t\t\t\t\t\t\t <div class=\"licensing\"><div class=\"license-attribution-dropdown-subheading\">CC licensed content, Shared previously<\/div><ul class=\"citation-list\"><li>Research Methods in Psychology. <strong>Provided by<\/strong>: University of Minnesota Libraries Publishing. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"http:\/\/open.lib.umn.edu\/psychologyresearchmethods\">http:\/\/open.lib.umn.edu\/psychologyresearchmethods<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA: Attribution-NonCommercial-ShareAlike<\/a><\/em><\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section>","protected":false},"author":23485,"menu_order":1,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Research Methods in Psychology\",\"author\":\"\",\"organization\":\"University of Minnesota Libraries Publishing\",\"url\":\"http:\/\/open.lib.umn.edu\/psychologyresearchmethods\",\"project\":\"\",\"license\":\"cc-by-nc-sa\",\"license_terms\":\"\"}]","CANDELA_OUTCOMES_GUID":"","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-69","chapter","type-chapter","status-publish","hentry"],"part":67,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/chapters\/69","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/wp\/v2\/users\/23485"}],"version-history":[{"count":0,"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/chapters\/69\/revisions"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/parts\/67"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/chapters\/69\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/wp\/v2\/media?parent=69"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/pressbooks\/v2\/chapter-type?post=69"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/wp\/v2\/contributor?post=69"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-geneseo-psychologyresearchmethods\/wp-json\/wp\/v2\/license?post=69"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}