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Single case designs are studies which are most commonly used by clinical and neuropsychologists. They require very few participants, often the participant is their own control, in these cases there is only the need for one participant (http://www.psychmet.com/id15.html). While the group design is the more classical style, where there are more participants, and normally they are split into groups with one group acting as the control for the study. Although the single case design is less used, and there are limitations to the applications of the data obtained because of the limited internal and external validity, they are a useful tool especially in some applications.

One of the main uses to single case designs is that they are very useful in the formulating of hypotheses. Due to the small number of participants needed it means that potential hypotheses, ideas and study designs can be tested to check they are viable before finding a larger population. This also means that the single case designs can be used in conjunction with group designs, either as a starting point, or to check the method of the study among other things.

Another advantage to the single case design is that it makes it possible for psychologists, and other researchers to study rare events. A single case design would be the most appropriate, if not the only method suitable for researchers to study someone who is suffering from a rare psychological disorder; or someone who is about to undergo some form of operation or treatment so they would be their own control. For example if a researcher was looking at the effects of having the corpus callosum cut, which is used as a cure epilepsy, then the control for the participant would just be themselves before the operation.

However, while the small number of participants used, or the fact that only one participant is needed for the single case design is an advantage it also is a disadvantage. The small number of participants means that any data collected has very limited external validity, so it is difficult to apply to larger populations. There is also a higher chance of bias occurring when researchers explain the outcomes; these can be due to observer biases, with the researcher only seeing what they think they should be seeing, or due to biases in the data.

Although single case designs have some draw backs, such as limited validity they can provide very useful insight into rare situations or disorders. They can also be successfully used to aid and add extra data to group design experiments. So they can be a useful tool for researchers so long as they when conclusions are drawn from them their limitations are kept in mind.

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The Placebo Effect

“Sometimes I believe more than six impossible things before breakfast…”

Stardate 205319: Weekly Blog. Should Psychology be written for the layman or should science be exclusively for Scientists?science b

Why do we laugh…

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Correlation and causation are often misused and muddled up, especially by people who are not as familiar with statistics. This is because causality and correlations is not the same thing, and if two variables have a correlation it does not mean that they have causality. The mix-ups can result in variables being said to cause one another, when in fact they just have a similar relationship.

Correlation between two variables is a number that is used to describe the strength of the relationship (http://www.socialresearchmethods.net/kb/statcorr.php). It is a statistic that enables people to describe the direction, indicated by whether the value is positive or negative; and magnitude of a relationship, with 1.0 indicating a very strong consistency and 0.0 meaning a very weak relationship between the two variables. So for example would be the relationship between ice cream sales and sun cream sales, both of the variables increase and decrease around the same times in the year, so they have a correlation. Whereas causality is described as the relationship between two variables, when one variable causes another variable to change in some way, and researchers investigate to see if changes in the variable would result in another variable also changing (http://psychology.about.com/od/researchmethods/ss/expdesintro_4.htm).

Correlation does not signify causality; this is for a number of reasons. One of the problems is that with assuming correlations are equivalent to one variable causing another is that is impossible to say which variable causes another. A study was done that looked into the relationship between depression and the smoking of marijuana in adolescents (http://www.aboutjuveniledelinquents.com/AJD/which-came-first-marijuana-use-or-depression.htm). It was found that there is a correlation between the two; however it is incorrect to state that one caused the other. The study did not show that smoking marijuana resulted in depression, or that people who were suffering from depression smoked marijuana. The two variables could be caused by an entirely different factor, and only have a correlation because of it. In the same way that is would be incorrect to say that buying ice cream made you buy sun cream, or vice versa. Both ice cream and sun cream buying are influenced by the seasons and one does not cause the other.

 So in conclusion, correlation does not signify causality however it may be useful for determining the cause of the variables or what causes them to change.

The internet has the potential for being used as a very large and extensive source for a variety of different data that could be applied to a number of different fields both in and out of psychology. It comes in a variety of forms, ranging from social networking sites, blogs, and videos to just name a few. With this wealth of potentially rich data that can be used for a variety of different studies it does raise the questions as to whether psychologists should be allowed to use this information in studies, and whether it would be ethical to be used as a way of collecting data.

Due to the nature of the way data from the internet is often collected it causes ethical problems, these mainly come in the form of it being difficult to fulfil the ethical code of conduct for psychology. The code of conduct describes how all participants have to give fully informed consent to take part in the study, this links into the principle that says that participants must not be deceived about the purpose of the investigation, however if any deception occurs then the participant cannot give their fully informed consent. Participants must be debriefed at the end of the study; all participants have the right to withdraw at any point in the study and for their data to be kept completely confidential with no way for the names of the participants to be linked with their data. (http://www.simplypsychology.org/Ethics.html)

One of the main ethical problems that can occur with using information from the internet is that in many cases it is anonymous, or it is very difficult to get in contact with the author or creator. This means that obtaining consent can be difficult if not impossible for the researchers, debriefing the participants is also difficult for the same reasons. Although it could be argued that because people had put the information publically then they are aware of the potential for it to be used. If it was private, and they did not want it people to see it they would not have put it up on the internet, though it can be argued that just because people put it on the internet does not mean that they would be happy with it being used as data in a study.

Data from the internet can be very useful, but also full of pitfalls and ethical dilemmas; because of this, researchers need to approach it with a sense of caution.

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Should psychology be written for the layman or should science be exclusively for scientists?

The three different ways to conduct a t-test

Post hoc ergo propter hoc

Blog about blogs – literally!

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To begin with it would probably be better to describe what the “file drawer problem” is, before attempting to look at why it is a problem in psychology and other areas of research.

The “file drawer problem” was a term that was first used by Rosenthal in 1979 (http://www.jstor.org/pss/3546355). It is used to describe the publication bias that can occur when it comes to studies that want to be published in peer review articles, or journals. It describes the tendency of studies with significant results being published over those that did not have produce statistically significant results (http://www.scientificexploration.org/journal/jse_14_1_scargle.pdf). So it could mean that the majority of the literature that gets published is that which has a statistically significant result; and the studies that do not have a statistically significant result metaphorically, sit in the researchers file drawer collecting dust.

The publication bias can be a problem because it can result in the public or the scientific community getting the wrong impression or understanding about the study or what the results indicate; it could also alter the reliability of the conclusions. For example there has been in recent years an influx on advice about what types of foods will help increase people’s memory and general health. One of the main foods that have featured has been blueberries. According to studies, eating blueberries helps to increase your memory along with reduce the chances for illnesses such as dementia in later life (http://www.garynull.com/storage/pdfs/scholarlyjournalarticles/SuperFoods_2011.pdf). However, due to the “file drawer problem” you cannot be sure if the evidence for blueberries helping your mental health is completely accurate and as conclusive. This is because there may have been studies that did not reach the same conclusion, and found no significance; but due to the publication bias were never published and made accessible for the scientific community or the general public.

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Qualitative research isn’t as scientific as quantitative methods.” week 9

Qualitative research or quantitative research…Which is better?

What’s the better, perhaps more scientific method, quantitative or qualitative?

What role does the null hypothesis REALLY play in the scientific process?

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First of all outliers are pieces of data, or data points that are extremely different from the rest of the other data in the sample. What qualifies as a an outlier varies from data selection to data selection, however if a data point is a several standard deviations away from the mean, or follows a completely different pattern to the other data points; then it is often considered an outlier. When outliers are identified, in many cases they are then removed from the data completely and therefore are not reported in the final write up. This could be considered dishonest because the researchers could be seen as altering the data; however in quite a few cases outliers are caused by mistakes done by the participants or researchers, and so removing the outliers are cleaning the data as the results that are being removed are not valid for the research.

Outliers, if they are left in the data can affect the statistics of the sample. They can alter the mean and variability of the sample, and therefore alter our ability to interpret statistical tests. In many cases outliers are caused by participants misunderstanding the task or by researchers making mistakes and therefore it can be argued that the outliers have no bearing on the actual conclusion because they are not valid results. For example in a study that was done by Janine Willis and Alexander Todorov (2006) was researching whether time constraints altered perceptions of people just from looking at their faces. Outliers in the study could have been caused by participants misreading what personality characteristic they were supposed to be identifying, and as such these outliers are not valid pieces of data. Since they are not valid bits of data it means that removing them is not dishonest as they hold no bearing to the research.

However in some research, especially qualitative studies, outliers can be just as informative as the other bits of data that fits to the pattern of the majority of the data. Barbara Michener and Marcia J Belcheir did a study that was looking into the first impression of freshman when they were first arriving at university. The participants took part in a number of interviews and group meetings in order for their first impressions to be accurately recorded. The majority of the participants felt that they had little to no problem adjusting and that the university provided a great deal of help and support making their transition easier. However there were a few students who took part in the study who did not find that the university was very helpful and struggled with the transition. The students who did not find the move easy, and the data that they provided, could be described as outliers, because they do not follow the trend of the majority of the data. If the researchers were to remove those pieces of data it could be considered dishonest, because although the pieces of data are outliers they are relevant and valid to the research.

When it comes to the removal of outliers from data it tends to depend on the researchers discretion as to whether removing them could be considered dishonest. The removal of outliers is subjective because it depends on the type of research and the design of the study, along with the type of data and conclusion that the experimenter is looking to form. As such, whether the removal of outliers is dishonest, in my opinion, it is also as subjective as whether outliers are outliers or not.

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The Helsinki Convention and subsequent declaration took place in June 1964 in Helsinki, Finland and was adopted by the World Medical Association. Since the first printing it has been refined six times, the most recent in 2008, and has been extended from 11 paragraphs to 32. The convention focussed on and produced a selection of ethical principles that apply to the medical community, in particular medical research. The Helsinki convention and the five basic ethical principles were based and a continuation on from the Nuremberg code.

The Nuremberg code was a set of ten principles that were created following the revelation of the war crimes that took place during the Second World War. The guidelines are for the ethical treatment for human participants in research, and the aim was to try and prevent the unethical research that had occurred, for example some of the experiments that occurred in the Nazi concentration camps during the war.

The first of the ten principles that the Nuremberg code decided on was that all human subjects must give voluntary consent before taking part in form of research or experiment. This means that the person who is running the research has the job to make sure that the participant has full knowledge and understanding of all facets of the experiment and all that it entails. They also have the right to refuse if they do not want to take part in the research and should not feel pressured by any outside force, whether it is the experimenter or anyone else. The second guideline is that the research must have a purpose, and the result of the research will be applicable and useful for society and the potential risk should be outweighed by what the research could bring to society. Next was the principle that stated that research should have been performed on animals before being performed on human participants. This is mainly aimed at medical research or pharmaceutical production. One of the principles is that during experiments should be conducted in a way to minimise potential harm to candidates; this is then followed by the principle that says that if there is any risk of death or any permanent injury then the experiment should not take place (of course there are exceptions, as if it is a surgical procedure then there is always the risk of death). Proper preparations should be provided for each experiment, and the experiment should only be performed by a fully qualified professional in that field. Finally the participant has the power to terminate the experiment at any given time if they should wish, and the researcher has to be prepared for that; also if at any point the experiment could become harmful to the participant the researcher should terminate the experiment (Research Methods for the Behavioural Sciences, Gravetter and Forzano).

From these ten guidelines the Helsinki convention produced the five principles that provide the main core for ethics in psychology. The first of these five principles is in all research fully informed consent must be obtained from the participants before any research can begin. Like with the Nuremberg code this means that participants must be fully aware and understand what is going to happen; so what is being researched, how it might affect them, the method etc. This particular principle can often cause dilemmas, because often in psychology if you were to tell the participant what you were measuring it would alter the results or the responses given. For example the research done by Fein and Spencer (1997) into whether prejudice is used by people to maintain their self-image. When they were doing the investigation they couldn’t tell the participants that they were researching how their self-esteem affected how positively they described the photos of people, as it would have affected how they rated them which would have made the results unreliable. Although the deception didn’t cause the participants any harm, they still did not obtain fully informed consent as the participants were not fully aware as to what the experiment entailed. This is also difficult with studies that include children or vulnerable adults. In these cases a loco parentis may be needed to give consent along with or instead of the participant.

The second of the five basic ethical principles is that the participant has the option to withdraw from the experiment at any point they want to. This principle allows the participant to have the freedom to leave if they feel uncomfortable without any repercussions. However it is a bit frustrating for those who are doing the study, as often that participants’ data then cannot be used. This again though has a potential issue, especially when the study is involving children as it is often difficult to judge whether they actually want to withdraw. As rule of thumb it is often considered withdrawal if the child avoids the situation (Ethical principles for conducting research with human participants, found at: dcs.gla.ac.uk/ethics/bps-conduct.pdf). Another of the basic ethical principles states that the participant must be protected from harm throughout the duration of the experiment. Harm includes both mental and physical, and the aim by researchers is for participants to leave the experiment with the same or better frame of mind when compared to the beginning of the study.

At the end of the study the investigator has to debrief the participant, this consists of the investigator filling in any blanks the participant may have over the nature of the research and any misconceptions that may have occurred. The last of the five basic ethical principles is concerned with the participants’ confidentiality. All the information provided by the participant should be kept confidential unless they have given express permission stating otherwise.

The Helsinki Declaration and the five basic ethical principles are all in place to protect participants who may take part in any form of research. Although they are very thorough and can be applied to all different types of psychological research there is research which is not clear cut as to whether it can be considered ethical, for these occasions there are committees whose sole purpose it is to say whether a proposal is ethical or not. This can be a minefield.