Experimental Methods 2/9/18. What is an Experimental Method?

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1 Experimental Methods Joseph Alvarez, Vanesa Castro, Liliana Hernandez, Marissa Silva What is an Experimental Method? Maniplating one variable (IV)to see if the change in one variable cases the other variable (DV) to change Operational definition Define the variables Random sample and Random assignment Random Sample - Poplation Random Assignment - Grops Control Grop Experimental Grop Experimental Control When are Experimental Methods best sed? They re best sed in the following experiments: Lab Experiments Field Experiments Qasi-Experiments 1

2 What are its weaknesses and strengths? Weaknesses May lead to bias Lack of external validity Can t stdy anything that is not maniplated Yo can't maniplate a false Independent Variable Demand characteristic There cold be a featre that might inform participants of the prpose of the stdy. This may lead to change in participants behavior Strengths Very basic and straightforward research Experiments can be repeated and reslts can be re-tested by other researchers. Control of extraneos variables It eliminates confonding third variables Randomization: This eliminates the inflence of extraneos variables Example 1: Asch Conformity Stdy (1951) The prpose of this experiment was to investigate the extent to which social pressre from a majority grop cold affect a person to conform. Asch sed a total of 50 male college stdents and did 12 trials that always had seven confederates and one naive participant. Strengths: This experiment was controlled and scripted to the most minte detail to get the most accrate reslts. By doing this it made the experiment free of participant bias and very easy to replicate in another stdy. Weaknesses: Only selected a sample of participants from a certain age grop and gender so this can limit the accracy of the reslts. No correct answer. Example 2: Milgram Experiment (1961) The prpose of this experiment was to test the conflict between obedience to athority and personal conscience. Milgram had 40 males between the ages 20 and 50 to participate in this experiment and one confederate. Strengths: Very basic and a step by step experiment that can be repeated by other psychologists. Weaknesses: The experiments setting and the sitation the the participants were pt in, were nrealistic which can case biased or nrealistic behavior. This can case the prpose of the experiment to go not be flly expressed. 2

3 Example 3: The Marshmallow Test (1972) The prpose of this experiment was to explore the the hman ability to delay gratification and how it affects a person's actions, emotions and decisions in life. Mischel tested this idea by sing a large grop of preschoolers and sing the marshmallow test. Mischel later tracked them throgh their life as teenagers and than 59 participants in their forties to see if his idea of delayed gratification was tre. Strengths: This experiment is easily repeatable and can be tested by other psychologists. Weaknesses: Very expensive and long experiment becase yo are following a large grop of participants throghot their lives. Sorces American Psychological Association. Delaying Gratification. APA, Cherry, Kendra. What Is the Experimental Method? Verywell, 9 Nov. 2017, Cherry, Kendra. 5 Important Steps for Condcting Psychology Experiments. Verywell, 2 Jan. 2018, Random Sampling vs. Random Assignment. Statistics Soltions, 28 Jly 2017, Experimental Control. Psychology Wiki, psychology.wikia.com/wiki/experimental_control. McLeod, Sal. Sal McLeod. Milgram Experiment Simply Psychology, 1 Jan. 1970, McLeod, Sal. Sal McLeod. Simply Psychology, 1 Jan. 1970, Tner, John. Qasi-Experiments. ttor2, Trner, John. Field Experiments. ttor2, Trner, John. Lab Experiments. ttor2, 3

4 Srvey Methods Angelica Gines, Jlio Oliva, Elmer Franco, and Jerricka Lindsey What is it? Srvey methods sally involves a qestionnaire or a series of qestions to distingish different people s attitdes, beliefs and behavior towards a sbject or mltiple sbjects. Usally generalized from a sample to a poplation Randomized = Eqal chance Sampling Styles Probability Sampling Simple Random Systematic Random Stratified Random Clster Non-probability Sampling Qota (Convenience/Haphazard Sampling) Whoever and whatever is available Snowball Self-selection 1

5 What types of srveys are there? 5 types of srvey designs Mailed Srvey Grop Srvey Phone Srvey In-person Interview Electronic Srvey Interviews Face To Face Interviews Advantages Empathy & Personal Interaction Body Langage Experiencing prodcts in real life Telephone Interview Advantages Wide Geographic Access Cost Time-Effective Disadvantages Higher costs Time consming Interviews can deliver biased response Disadvantages Less Control Yo have to be very brief What the Srvey Method is Best Used For Condcting srveys is an nbiased approach to decision-making. Yo can collect srvey data and develop sensible decisions based on analyzed reslts. Time-efficient; responses are easy to code and interpret; ideal for qantitative type of research Mltiple methods give greater nderstanding of behavior 2

6 Weaknesses of the Srvey method Srvey can become inflexible and irreversible if the data collected is nsatisfactory and there is no time for a do-over or reformatting Confsing phrasing can affect participants responses Lack of validity Fence sitting (indecisive between yes and no) Possibility of not obtaining a representative sample Bias in the srvey Examples 1. Who is more likely to pt off medical treatment? (Gallp Poll) - Sbjects: Random sample of 1,028 adlts, ages 18 and older, living in all 50 states and the District of Colmbia - Method: Telephone interviews were condcted from Nov 2-8, 2017, - The sample inclded a minimm of 70% cell phone respondents and 30% landline respondents. The time zone of the region was taken into accont a well. In order to get this sample, random-digital-dial methods were sed. - Reslts: 22% of women pt off medical treatment in comparison to men who refsed treatment 37% of the time. - The margin of sampling error is ±4 percentage point at the 95% confidence level Examples Strengths of stdy: - Random-digital-dial methods are a form of simple random sampling, one of the best ways to acqire a diverse and completely random representative sample Weaknesses of stdy: - Not all adlts have telephone access whether it be cellphone or landline - Althogh reasoning behind why the men and women resisted treatment was stdied, demographics that cold case this reasoning were not reported on. - Ex: Women were reported to resist treatment based on cost more than men, bt the socioeconomic stats of the participants wasn t fond. This means that socioeconomic stats cold be why people resist treatment, not solely gender differences. 3

7 Examples 2. Adlts vs. Teens: who texts and drives more often? (CNN and AT&T) Sbject: 1,011 adlts and 1,200 teen drivers who own cell phones Methods: Srvey was provided throgh a link on AT&T s website. The adlt srvey was provided in March of The teen srvey was provided in April of drivers Reslts: 49% of adlts admitted to sending a text behind the wheel in comparison to 43% of teen Examples Strengths of the stdy: - The sample was relatively large with a total of 2,211 sbjects. Weaknesses of the stdy: - The sample is not a representative sample as convenience sampling was sed. The link to the srvey was simply posted on AT&T s website. It was not random by any means. - Response Bias: - Idea that those who respond to polls are different from other people - Will people really admit to texting and driving? - The different srveys weren t given at the same time. Examples 3. Impact of social media sage on daytime sleepiness Sbject: 969 tertiary stdents from a tertiary instittion in Singapore. 1,049 stdents were srveyed, bt 80 sbject responses were thrown ot de to incomplete srveys Method: a srvey that contained qestions concerning demographic data, daytime sleepiness, total sleep time and social media sage was handed ot to the stdents that agreed to participate Reslts: Local Singapore stdents spent significantly more time on social networking sites at night compared to foreign stdents. As a reslt, local stdents experienced more daytime sleepiness compared to foreign stdents. 4

8 Examples Strengths of the stdy: - The srvey inclded many different qestions that cold reslt in many different findings Weaknesses of the stdy: - Representative sample? - Are all stdents affected in the same way as stdents in Singapore? - Not random, convenience sampling is sed by only srveying stdents from one instittion Works Cited Gallp, Inc. "Americans' Spport for Death Penalty Stable." Gallp.com. N.p., 23 Oct Web. 06 Feb Gallp, Inc. "U.S. Women More Likely Than Men to Pt Off Medical Treatment." Gallp.com. N.p., 06 Dec Web. 06 Feb Gross, Dog. "Srvey: Adlts Text More than Teens While Driving." CNN. Cable News Network, 28 Mar Web. 06 Feb Nasirdeen, A M A, et al. Impact of Social Media Usage on Daytime Sleepiness: A Stdy in a Sample of Tertiary Stdents in Singapore. Digital Health, vol. 3, 2017, p , doi: / Non-probability Sampling Lærd Dissertation. N.p., n.d. Web. 06 Feb "Principles of Sociological Inqiry: Qalitative and Qantitative Methods, v. 1.0." FlatWorld. N.p., n.d. Web. 06 Feb "Psychology: Srvey Method & Natralistic Observation." SchoolWorkHelper. N.p., n.d. Web. 06 Feb

9 Natralistic Observation Methods Moryn Hagee, Hector Isas, Erik Sanchez, and Anshil Bhatt What is natralistic observation methods? Behavior is observed in its natral setting Psychologists watch behavior occr Note down observations and analysis Unobtrsive - observer does not alter or inflence environment No maniplated variables What is the method best sed for? Best sed for natral reactions No behavior change from nnatral settings Qalitative research Cost effective External validity Ethical - e.g. prison 1

10 Drawbacks/Weaknesses The behavior of participants might change when they get aware that they are being observed - Hawthorne Effect. Time consming, as it may take more time for the participant to express the particlar behavior we are targeting- large sample needed. Interrater Reliability - Conflict among the researchers or disagreement with the reslts they obtain after an observation. The observer is observing throgh his lens, he is interpreting so the direct representation of reality is not possible. Driving Psychology: Facts of stdy Examining trn signal se inflenced by car color and presence of window tint Hypothesis: Regardless of color of car, if tint is present then driver is less likely to se their trn signal Research condcted in Trlock, Modesto, and Salidas, California Observed 1,611 cars Hidden from drivers: sitting at bs stops, otside starbcks, etc. Pro s for natral observation: Drivers react natrally No demand characteristics See behavior first hand Con s for natral observation: No information on participants, other than what is observable Can not control for confonds Operational definitions hard to determine Social Desirability 2

11 Jane Goodall Chimp Stdy Began her stdy in 1960 at Gombe Stream National Park in Tanzania. Followed and docmented their habits. Lived with them and stdied their behavior and personalities. Challenged two myths The idea that only hmans can se and make tools. The belief that chimps were passive vegetarians. One weakness was that she bilt a feeding station to lre chimps bt later fond that it slightly altered their behaviors. Graham and Wells (2001) Observed 117 aggressive incidents over a 93 day period Observed bar patrons at a Canadian Bar Patrons were naware of being observed Able to identify triggers for aggressive behavior (problems with bar staff, rowdy behavior, etc)) Confonding variable? Personality of participant? References Natralistic Observation. Natralistic Observation, 31 Jan. 2007, peace.samag.ed/faclty/kardas/corses/rmpa/natralisticobservation.html. Graham, Kathryn, et al. Apparent Motives for Aggression in the Social Context of the Bar. Psychology of Violence, U.S. National Library of Medicine, 1 Jly 2013, Kendra Cherry, et al. The Pros and Cons of Natralistic observation. VeryWell, 4 Nov Strctre, Strengths And Weaknesses In Observation. UKEssays, 23 March Jane Goodall's Wild Chimpanzees. PBS, Pblic Broadcasting Service, 27 Oct. 2014, 3

12 Case Stdy Methods Presented by Rebecca Hernandez, Chandler Rosenow, Jennifer Venegas, and Carlos Gonzalez Rvalcaba Case Stdy An in depth assessment of a person, grop or event that has been stdied extensively over time. Case stdies often involve collecting descriptive information abot a particlar person, so developments and processes can be stdied while they occr. Sorces of data inclde observation of a person s daily rotine, nstrctred interviews with the participant, diaries, personal notes, employer reports, psychological test reslts, comments from those closest to the person, or official docments. Most information is qalitative bt nmerical data can work as well. The information is typically biographical and relates to events in the individals past as well as important events that are occring in his or her everyday life. Little Albert experiment Short Smmary: The Little Albert Experiment demonstrated that classical conditioning the association of a particlar stimls or behavior with an nrelated stimls or behavior works in hman beings. In the experiment, psychologist John Watson was able to condition a previosly nafraid baby to become afraid of a rat. Classical conditioning plays a central role in the development of fears and associations. Or Thoghts: The Little Albert experiment is a famos example of a poplar case stdy and how they are typically condcted. The advantage of choosing a case stdy for this specific experiment is that they get to focs solely on their sbject Albert and record all observations they saw inclding all of Abert s enconters with the rat from the initial start of the experiment to the conclsion of it. On the other hand John B. Watson has nothing to compare this stdy with meaning the lack participants cold indicate that the experiment was a flke, which is a major weakness of choosing a case stdy. By choosing a case stdy thogh, Watson was able to isolate whichever factors he pleased and had fll control of the entire stdy. 1

13 Case Stdy Method The case stdy method is best sed.. Widely in clinical psychology - The ltimate prpose is for psychologists to seek in depth information abot the hman brain, behavior, or cognitive thinking To observe what happens to a participant or to reconstrct a case history of the participant - This approach plays a significant role in diagnosis and in the planning of therapy or treatment Jill Price Short Smmary: Jill Price is one of the very few patients with hyperthymesia, an incredible memory that allows her to remember nmeros obscre aspects of her life in incredible detail. She can, for example, remember what she had for dinner 20 years ago, on an ordinary Agst afternoon. This ability has cased her significant emotional trama de to her remembrance of every derogatory remark or tramatic event in her life. Jill Price is still participating in psychological stdies that hope to shed light on her condition. Or Thoghts: In this case stdy Jill Price is being evalated by many different psychologists in fll depth to help reach conclsions abot her rare condition. Unlike Watson and the Little Albert experiment, Jill Price being stdied by mltiple different people is great for comparing data and drawing conclsive reslts and becase case stdies are so in depth, this means that there is a variety of data to compare. A potential downside to this is that each researcher may be condcting their experiment in a different way so they may be isolating and testing different variables which in trn wold make it harder to compare reslts. Genie the feral child Short Smmary: Genie is a relatively recent example of a feral child. Feral children are hmans raised in social isolation, experiencing little or no hman contact in their lives. Feral children are typically the reslt of either child abandonment or abse. De to malnorishment and lack of mental stimlation, feral children never flly cognitively develop. Genie was sch a child. Fond in 1970 at the age of 13, Genie had spent most of her life confined in a bedroom, strapped to a potty chair. Her father had believed she was mentally ill, so he took steps to protect her. He beat her every time she made a sond. Her physical and mental development was stnted, and she never learned to speak or walk properly. Or Thoghts: This is an example of a long spanning case stdy where one is able to stdy someone for a long time withot the complications yo get when yo have a large sample size. The lack of sample size does mean we can t accept everything as a conclsive trth bt with this being sch a rare case, it is virtally impossible to get similar participants withot breaking the IRB s rles and gidelines. Long lasting stdies can be very costly bt in this instance, it is far cheaper to have to only invest into one sbject, making a case stdy the most appropriate method of research for an experiment like this in or opinions. 2

14 Weaknesses of Case Stdies Time Intensive Possibility of Errors Ethical Isses Researcher Bias Inability to Replicate Sorces For Presentation Little Albert and Jill Price: Psychology's 10 Greatest Case Stdies Digested. Research Digest, 15 Dec. 2017, digest.bps.org.k/2015/11/27/psychologys-10-greatest-case-stdies-digested/. Genie the feral child: Five Landmark Psychology Case Stdies Yo Shold Know Abot. The Greatest Blog in the Universe, 2 May 2011, abdllaman.wordpress.com/2011/05/01/five-landmark-psychology-case-stdies-yo-shold-know-abot/. Advantages and Disadvantages of Case Stdies. psd43, 19 Feb. 2012, psd43.wordpree.com/2012/02/19/advantages-and-disadvantages-of-case-stdies/. Case Stdy Method. Sal Mcleod, Simply Psychology,

15 Archival Research By Ayana Nno, Crystal Crz, Lzpaola Espinoza, Yaritza Ochoa-Solorzano What is Archival Research? Archival research is a method of collecting data from sorces that already exist. Most data is coming from private companies and/or government Methods When yo want to access large amont of information that sed Archives Polls Statistics Having information that provides the ability to have a large nmber of hypothesis yo can test Google trends 1

16 Examples Trends on Google; A list of the most searched terms on google Examples Con t Ex: Determining that more batters are hit by a pitch on hot days than on cooler days by comparing baseball statistics and daily temperatre Strengths It does not face a problem with participant reactivity Less time consming and less expensive Digital copies 2

17 Weaknesses Hard copies Research may be nreliable No control of how data is collected Data may be incomplete References Archival Research. Archival Research Definition, Archival Research. Wikipedia, Wikimedia Fondation, 5 Feb. 2018, en.wikipedia.org/wiki/archival_research Data Collection Methods, 2 Mar. 2017, "What are the advantages and disadvantages of sing the archival method?" enotes, 20 Apr. 2012, 3

18 Correlational Methods Rachel Tai, Amy Stewart, Seth Trovao, and Shyan Crtcher What is Correlational Methods ACCORDING TO SIMPLYPYSCHOLOGY.ORG, A CORRELATION IS DEFINED AS THE PRECISE MEASURE OF THE EXTENT TO WHICH TWO VARIABLES ARE RELATED HOWEVER, CORRELATION IS NOT USED AS A RESEARCH METHOD CORRELATIONS ARE USED TO ANALYZE THE DATA COLLECTED. TYPES OF CORRELATIONAL RESEARCH INCLUDE SURVEYS OR NATURALISTIC OBSERVATION. Types of Correlation There are three types of correlations: Positive, Negative, and No correlation These three types of correlations are commonly shown visally and/or nmerically A scattergram or scatterplot is sed to express correlations visally by sing an x and y axis and plotting the figres on the graph accordingly The Correlation Coefficient, (r), is sed to express correlations nmerically from to +1.0 (r)= 0.9, 0.8, 0.7 the correlation is strong and positive (r)= -0.9, -0.8, -0.7 the correlation is strong and negative (r)= -0.6, -0.5, -0.4 and 0.4, 0.5, 0.6 are moderate (r)= 0.1, 0.2, 0.3 and -0.1, -0.2, and -0.3 are weak When the coefficient 0, the the correlation is nonexistent 1

19 Positive Correlation A positive correlation is when one variable increases, the other variable increases as well (r)= 0.1 to 1.0 Negative Correlation A negative correlation is when one variable increases, the other variable decreases (r)= -0.1 to -1.0 No Correlation A non-existent correlation means that there is no connection between the two variables (r)=

20 Why is Correlational Research Important? Psychological research is generally performed one of two ways: throgh experimental research, or throgh correlational research Experimental research is sally research that is performed in a laboratory setting in which variables are maniplated and measred. Correlational research, on the other hand cannot determine casal relations, that is it is not sed to determine casation Correlational research is sed to show the relationship, if any, between two variables and is sed to discover more information abot what may or may not be linking these variables together. Why is Correlational Research Important? Two variables that show relations may not actally be linked, however. Some correlations exist between events that are completely nrelated otherwise. EX: One cold say that low self-esteem and depression rates are correlated: Low self-esteem cold case depression. However, depression cold case low self-esteem, or otward environmental effects or biological predispositions cold also case low self-esteem OR depression. Thogh correlations exist, it does not necessarily mean that one variable directly cases the other. Why is Correlational Research Important? Thogh Correlational Research does not necessarily determine casality, the research itself is qite sefl. Drg companies se correlational research to determine the rates at which a proposed new drg might case side-effects and what those side effects might be. Correlational research is also incredibly sefl for making predictions. Once a researcher knows that two variables are somewhat correlated, he or she can predict the way that the variables interact, as well as how changes in one might case reactions in the other, and vice versa. Lastly, correlational research can also lead to the formation of new hypotheses and experiments. These correlations cold potentially expose important experimental relationships between variables that might not otherwise have been discovered. 3

21 Weaknesses of a Correlational Stdy Does not imply casation We CANNOT assme one variable cases the other Ex. Dring the smmer time, ice cream sales increase as crime rate increases. Information that is given is all that can be inferred An otside variable may be the case of both inclded variables Examples of Positive Correlation A Job s Wage vs Likeliness to Stay Level of Yoth Achievement vs Level of Adlt Achievement Caffeine vs Cognitive Performance (nder particlar conditions) Examples of Negative Correlation Stdents Non-Medical Use of Stimlants vs Sleep Qality and GPA Smoking vs Lng Health Time Absent vs Sccess in School 4

22 Examples of No Correlation Power Posing vs Improvement in Social Anxiety dring Pblic Speaking High Income vs Sense of Meaning in Life Handwriting Legibility vs Intelligence References Arria, A. M. (2011). Compromised sleep qality and low GPA among college stdents who se prescription stimlants nonmedically. Sleep Medicine,12(6), doi: /j.sleep Coyle, T. R. (2015). Relations among general intelligence (g), aptitde tests, and GPA: Linear effects dominate. Intelligence,53, doi: /j.intell Davis, M. L., Papini, S., Rosenfield, D., Roelofs, K., Kolb, S., Powers, M. B., & Smits, J. A. (2017). A randomized controlled stdy of power posing before pblic speaking exposre for social anxiety disorder: No evidence for agmentative effects. Jornal of Anxiety Disorders,52, 1-7. doi: /j.janxdis McLeod, S. (2008). Correlation. Retrieved Janary 30, 2018, from Sn, Y., Zhang, Y., He, N., Li, X., & Miao, D. (2007). Caffeine and Placebo Expectation. Jornal of Psychophysiology,21(2), doi: / Wang, Y., & Yang, C. (2015). How Appealing are Monetary Rewards in the Workplace? A Stdy of Ethical Leadership, Love of Money, Happiness, and Trnover Intention. Social Indicators Research,129(3), doi: /s x Ward, S. J., & King, L. A. (2016). Poor bt Happy? Income, Happiness, and Experienced and Expected Meaning in Life. Social Psychological and Personality Science,7(5), doi: / What is Correlational Research Most Usefl For? BetterHelp. Retrieved from 5