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Chapter 2 Research Methods
Pages 20 – 41 in your textbook!
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The Need for Psychological Science
The biases and errors of people’s everyday judgments illustrate the need for: Skepticism Humility Critical Thinking
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Hindsight Bias: Hindsight Bias = The tendency to believe, after learning the outcome, that you knew it all along. Have you ever done this?
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Hindsight Bias examples:
After a long night out, two friends stop at a diner. One orders coffee and the other says, "you might feel tired now, but that’s gonna keep you awake, I bet." It actually happens, and the second friend insists that he was sure it would. Imagine that you receive a letter from a publisher that states that the publisher is going to publish your short story. You tell a friend that you knew that they would publish it. However, the friend reminds you that before you received the letter, you had told him that you were very uncertain about whether the publisher would accept your short story for publication.
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The Experiment: An experiment is an investigation in which a hypothesis is scientifically tested. In an experiment, an independent variable (the cause) is manipulated and the dependent variable (the effect) is measured.
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Experimental Method (take a picture if you don’t want to write all this down!)
Review Literature of Past Research Formulate Hypothesis Design Research/Study Method (naturalistic observation, case studies, surveys, experiments, etc) Collect the Data Analyze the Data Report the Findings (journal, critique, replicate) Draw Conclusion or Theory on Findings
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Experimental Method:
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Hypothesis: A statement about the relationship between two or more variables Must be testable and refutable Instead of proving the hypothesis, science usually tries to disprove a null hypothesis. Null Hypothesis (H0): opposite of hypothesis
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Hypothesis Example: H1: Gender has an effect on perceived intelligence H0: Gender does not have an effect on perceived intelligence
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Mean, Median, Mode, and Range!
I know we all know what this is but we are going to watch a video “recap” then take some pictures of some flash cards!
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Frequency distribution:
Frequency distribution = is a simple (basic, but not necessarily easy) type of statistic that people often make into a much bigger deal than it really is. Let's say you are in a class with 100 people, and you have just taken a test. The teacher then tells you that on the test, there were 20 "A"s, 25 "B"s, 35 "C"s, 15 "D"s, and 5 "F"s. What the teacher has just given you is a frequency distribution; a breakdown of how all the scores fell into the different categories or ranges that the overall score was broken into.
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Frequency distribution:
A function showing the number of instances in which a variable takes each of its possible values.
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Skewed: Skewed distribution is a statistical term that measures “asymmetry” (lack of similarity) in a “bell curve” (the bell-shaped graph that occurs when plotting data based on normal measured traits).
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Skewed: A distribution is skewed if one tail is longer than another. These distributions are sometimes called asymmetric or asymmetrical distributions as they don’t show any kind of symmetry. Symmetry means that one half of the distribution is a mirror image of the other half. The normal distribution is a symmetric distribution with no skew. The tails are exactly the same.
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Standard deviation: Standard Deviation is a measure of variation (or variability) that indicates the typical distance between the scores of a distribution and the mean. Standard Deviation is a measure of how spread out numbers are. Its symbol is σ (the Greek letter sigma)
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Normal distribution: Types of Distributions. When data sets are graphed they form a picture that can aid in the interpretation of the information. The most commonly referred to type of distribution is called a normal distribution or normal curve and is often referred to as the bell shaped curve because it looks like a bell.
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Normal Distribution: A normal distribution is symmetrical, meaning the distribution and frequency of scores on the left side matches the distribution and frequency of scores on the right side.
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Or it can be all jumbled up
Normal Distribution: Data can be "distributed" (spread out) in different ways. But there are many cases where the data tends to be around a central value with no bias left or right, and it gets close to a "Normal Distribution" like this: It can be spread out more on the left Or more on the right Or it can be all jumbled up
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Scientific Method:
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Confirmation bias: Confirmation Bias = occurs from the direct influence of desire on beliefs. When people would like a certain idea/concept to be true, they end up believing it to be true. They are motivated by wishful thinking. This error leads the individual to stop gathering information when the evidence gathered so far confirms the views (prejudices) one would like to be true.
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Confirmation bias:
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Confirmation Bias and how it impacts us:
A number of experiments conducted during the 1960s demonstrated that people have a tendency to seek information that confirms their existing beliefs. Unfortunately, this type of bias can prevent us from looking at situations objectively, can influence the decisions we make, and can lead to poor or faulty choices.
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Confirmation Bias and how it impacts us:
During an election season, for example, people tend to seek positive information that paints their favored candidates in a good light while looking for information that casts the opposing candidate in a negative light. By not seeking out objective facts, interpreting information in a way that only supports their existing beliefs, and only remembering details that uphold these beliefs, people often miss important information that might have otherwise influenced their decision on which candidate to support.
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Participation Bias: Participant bias occurs in psychology experiments when participants adjust their behavior to what they think the experimenters expect. This can be a significant problem in that, if participant bias occurs, then the results of an experiment may not be entirely due to the experimenters’ manipulation of the independent variable. For this reason, psychologists often do not inform their study’s participants of the experiment’s aims until post- experimentation. The act of not telling participants what the study’s aim until post-experimentation is called a single blind control.
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Single – Blind Research Method
The Single-Blind research method is a specific research procedure in which the researchers (and those involved in the study) do not tell the participants if they are being given a test treatment or a control treatment.
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Double - Blind Research Method
A double-blind study is one in which neither the participants nor the experimenters knows who is receiving a particular treatment. This procedure is utilized to prevent bias in research results. Double-blind studies are particularly useful for preventing bias due to demand characteristics or the placebo effect.
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Placebo effect: Also called the placebo response. A remarkable phenomenon in which a placebo -- a fake treatment, an inactive substance like sugar, distilled water, or saline solution -- can sometimes improve a patient's condition simply because the person has the expectation that it will be helpful. Expectation to plays a potent role in the placebo effect. The more a person believes they are going to benefit from a treatment, the more likely it is that they will experience a benefit.
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Placebo effect: To separate out this power of positive thinking and some other variables from a drug's true medical benefits, companies seeking governmental approval of a new treatment often use placebo-controlled drug studies. If patients on the new drug fare significantly better than those taking placebo, the study helps support the conclusion that the medicine is effective.
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Independent Variable (IV):
An independent variable, a term used in math and statistics, is a variable you can manipulate, but it's not dependent on the changes in other variables. The independent variable is usually indicated by "x" and the "dependent variable" is "y."
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Dependent Variable (DV)
Dependent variable (DV): Variable the experimenter measures, after making changes to the IV that are assumed to affect the DV.
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Example: (Independent variable) causes a change in (Dependent Variable) and it isn't possible that (Dependent Variable) could cause a change in (Independent Variable). For example: (Time Spent Studying) causes a change in (Test Score) and it isn't possible that (Test Score) could cause a change in (Time Spent Studying).
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Experimental & Control Group:
An experimental group is the group in an experiment that receives the variable being tested. One variable is tested at a time. The experimental group is compared to a control group, which does not receive the test variable. In this way, experimental groups are used to find answers in an experiment.
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Example: Cancer studies are a great example, say you have 50 people all about the same age 25 men and 25 women with the same type of cancer. Group A received the real cancer drug being tested Group B received the placebo After a few weeks / months the two groups data is compared and studied to see how effective the drug really is.
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The Importance of Randomization:
Random selection is the best way to choose the participants for any study. Participants must then be assigned to either the experimental or control group. Not surprisingly, random assignment of participants to one or the other condition is the best way to ensure control over other interfering, or extraneous, variables. Random assignment means that each participant has an equal chance of being assigned to each condition.
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Random assignments: Random assignment refers to the use of chance procedures in psychology experiments to ensure that each participant has the same opportunity to be assigned to any given group. Study participants are randomly assigned to different groups, such as the experimental group, or treatment group.
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Confounding variable:
Confounding variable (AKA third variables) are variables that the researcher failed to control or eliminate, damaging the internal validity of an experiment. This third variable can adversely affect the relation between IV and DV. This may cause the researcher to analyze the results incorrectly. The results may show a false correlation between the DV and the IV, leading to false data.
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In an experiment, the independent variable typically has an effect on your dependent variable. For example, if you are researching whether lack of exercise leads to weight gain, lack of exercise is your independent variable and weight gain is your dependent variable. Confounding variables are any other variable that also has an effect on your dependent variable. They are like extra independent variables that are having a hidden effect on your dependent variables. Confounding variables can cause two major problems: Increase variance Introduce bias.
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Let’s say you test 200 volunteers (100 men and 100 women)
Let’s say you test 200 volunteers (100 men and 100 women). You find that lack of exercise leads to weight gain. One problem with your experiment is that is lacks any control variables. For example, the use of placebos, or random assignment to groups. So you really can’t say for sure whether lack of exercise leads to weight gain.
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One confounding variable is how much people eat
One confounding variable is how much people eat. It’s also possible that men eat more than women; this could also make sex a confounding variable. Nothing was mentioned about starting weight, occupation or age either. A poor study design like this could lead to bias. For example, if all of the women in the study were middle- aged, and all of the men were aged 16, age would have a direct effect on weight gain. That makes age a confounding variable.
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Case Study: Case studies are in-depth investigations of a single person, group, event or community. Typically, data is gathered from a variety of sources using several different methods observation, interview etc.. The research may also continue for an extended period of time, so processes and developments can be studied as they happen. Case studies allow a researcher to investigate a topic in far more detail than might be possible if they were trying to deal with a large number of research participants.
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Naturalistic observation:
Naturalistic observation (i.e. unstructured observation) involves studying the spontaneous behavior of participants in natural surroundings. The researcher simply records what they see in whatever way they can. Compared with controlled/structured methods it is like the difference between studying wild animals in a zoo and studying them in their natural habitat.
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Naturalistic observation:
Sometimes all researchers need to know is what is happening to a group of animals or people. The best way to look at the behaviors of animals or people is to watch them behave in their normal environment. That’s why animal researcher Jane Goodall went to the areas where chimpanzees lived and watched them eat, play, mate, and sleep in their own natural surroundings. In order to study people, researchers might want to observe them in their work place, home, or even on a playground. Example: if a researcher wanted to know how teens behave with members of the opposite sex in a social setting, she might go to the mall on a weekend night.
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Naturalistic observation advantages:
It allows researchers to get a realistic picture of how behavior occurs because they are actually watching that behavior. In a more artificial setting like a lab they might get behavior that is contrived or artificial rather then genuine. But researchers have to be careful to not let the subjects know they are being watched. In many cases animals or people who know they are being watched will not behave normally this is called the observer effect. If you wanted to observe teens at the mall don’t sit with a pen, and paper in hand jotting down notes. Pretend to be reading a book or magazine and hide a small notepad inside it to jot down notes. Keep what your doing hidden!
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Your task…. You need to have a hypothesis of some type that you can test using naturalist observation Examples: Video one = Seeing if people will return money dropped in the mall. Video two = Seeing if 19 out of 20 people will high five when approached by a stranger.
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Your turn! YOU MUST WORK AS A TEAM
Keeping in mind what you have just learned about naturalistic observation, I want you to go out as a TEAM and get ready for your project instructions. I am going to hand out the instructions. Your going to make a short video of your process or type it up in a paper. Let’s watch what some other kids have done in the past brought to you by YOUTUBE!!!
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What is a Hypothesis? A hypothesis is a tentative, testable answer to a scientific question. Once a scientist has a scientific question she is interested in, the scientist reads up to find out what is already known on the topic. Then she uses that information to form a tentative answer to her scientific question. Sometimes people refer to the tentative answer as "an educated guess." Keep in mind, though, that the hypothesis also has to be testable since the next step is to do an experiment to determine whether or not the hypothesis is right!
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What are some of your ideas?
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Correlational study: Correlation means association - more precisely it is a measure of the extent to which two variables are related. If an increase in one variable tends to be associated with an increase in the other then this is known as a positive correlation. An example would be height and weight. Taller people tend to be heavier. ( > ) If an increase in one variable tends to be associated with a decrease in the other then this is known as a negative correlation. An example would be height above sea level and temperature. As you climb the mountain (increase in height) it gets colder (decrease in temperature).
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Correlational study: cont
When there is no relationship between two variables this is known as a zero correlation. For example their is no relationship between the amount of tea consumed and level of intelligence. A correlation can be expressed visually. This is done by drawing a scatterplot.
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Survey method: A survey is a data collection tool used to gather information about individuals. Surveys are commonly used in psychology to collect self-report data from study participants. A survey may focus on factual information about individuals, or it might aim to obtain the opinions of the survey takers.
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Population: Sampling is the process of selecting participants from the population. The target population is the total group of individuals from which the sample might be drawn. In psychological research we are interested in learning about large groups of people who all have something in common. We call the group that we are interested in studying our 'target population'. In some types of research the target population might be as broad as all humans, but in other types of research the target population might be a smaller group such as teenagers, pre-school children or people who misuse drugs.
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Random sample: Random sample = Every member of the population must have an equal chance of being selected to be a part of the sample. The selection of one member of the population is not dependent upon the selection of another member.
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Longitudinal study: A longitudinal study is an observational research method in which data is gathered for the same subjects repeatedly over a period of time. Longitudinal research projects can extend over years or even decades. In a longitudinal cohort study, the same individuals are observed over the study period.
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Cross-sectional study:
Cross-sectional research involves using different groups of people who differ in the variable of interest but share other characteristics, such as socioeconomic status, educational background, and ethnicity. Cross-sectional research studies are often used by researchers studying developmental psychology.
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Get your phones out I want you to take a pick of the following slide!
Picture time!!! Get your phones out I want you to take a pick of the following slide!
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Cohort effect: Cohort effect -- When people who were born at about the same time, such as during a given year or a particular decade, share various characteristics as a group (e.g., conservatism, credit card purchasing, home ownership, cigarette smoking). For example, the per capita consumption of alcohol has declined, partly because the cohort of people over 50 years of age, who tend to drink less, has proportionately increased.
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Sometimes we think we know more than we actually know.
Overconfidence: Sometimes we think we know more than we actually know.
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How long do you think it will take you to unscramble these anagrams?
WREAT = WATER ETYRN = ENTRY GRABE = BARGE How long do you think it will take you to unscramble these anagrams?
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People said it would take about 10 seconds, yet on average they took about 3 minutes
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Overconfidence a question:
So now that we know what this means, how do you think this could negatively affect an experiment, or study in this field?
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Overconfidence: Who knows someone like this?????? We all do
Please share your personal experience with overconfidence!!!!
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Critical Thinking: Critical thinking does not accept arguments, and conclusions blindly. It examines assumptions, discerns hidden values, and evaluates evidence and assesses conclusions. Critical thinkers ask questions like: How do they know that? What is the persons agenda? Is the conclusion based on a gut feeling or evidence? Critical thinking informed by science helps clear the colored lenses of our biases.
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The scientific attitude: curious, skeptical and humble:
Underlying all science is first a hard headed curiosity, a passion to explore and understand without misleading or being misled. Some questions (is there life after death?) are beyond science. Answering them in any way requires a leap of faith. With many other ideas (can people really read minds?). Magician James Randi has used the empirical approach when testing those claiming to see auras around people’s body, and those who claim to read minds.
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The amazing Randi: /watch?v=vJQBljC5RIo
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IRB: An Institutional Review Board (IRB) is a committee established to review and approve research involving human subjects. The purpose of the IRB is to ensure that all human subject research be conducted in accordance with all federal, institutional, and ethical guidelines.
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Informed Consent: Informed consent is a legal and ethical term defined as the consent by a client to a proposed medical or psychotherapeutic procedure, or for participation in a research project or clinical study.
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