Elements of researching behavior Flashcards
Independent measures design/between subjects design
the researcher deliberately wants the same people to be in both conditions
Repeated measures design/within subjects design
The experimenter randomly allocates participants into two groups. This is an effective design when your behavior of interest is assumed to be the same for everyone in the general population. One group would receive the experimental condition, whilst the other is the control group who do not receive the experimental condition
What is a hypothesis?
A hypothesis is a statement that serves as a possible explanation for observed facts. A hypothesis is tested empirically (practically) through trial and error that generates data
falsifiability in terms of hypothesis
A theory is based on the principle of falsifiability (developed by Popper (1959)). This principle means that we do not prove theories, we merely stay with the one that we have so far been unable to falsify
What is a research/experimental/alternative hypothesis?
It is the researchers expectation regarding the results of the experiment + usually suggests that the IV will have an effect on the DV
What is the null hypothesis?
is usually the hypothesis that the IV has had no significant effect on the DV and any observed differences in the conditions result purely from chance.
what are the One-tailed/directional and two-tailed (non-directional) hypotheses?
A one-tailed hypothesis is simply one that specifies the direction of a difference/correlation, while a two-tailed hypothesis is one that does not.
What is the p value?
It is only possible to reject the null hypothesis if a probability level (p-value) is set. The p-value shows how likely the result occurred by chance if the null hypothesis is true. If the results of the statistical test are smaller than the p-value, the null hypothesis can be rejected. If the results are larger than the p-value, the null hypothesis is accepted. In social sciences, the standard p-value is set at 0.05. This means the null hypothesis is only rejected if there is a 5% or less chance that the result happened by chance. This is written as p ≤ 0.05, indicating a statistically significant result. If p > 0.05, the result is not significant, and the null hypothesis is accepted. A significant result (p ≤ 0.05) allows the researcher to reject the null and accept the experimental hypothesis.
What is type I error?
Is known as a ‘false positive’. It occurs when the researcher rejects a null hypothesis when it is true. One way to check for type I errors is to replicate studies. Reducing P value comes with a higher risk of type II error
What is type II error?
is a ‘false negative’ and it occurs when the researcher accepts a null hypothesis that is false. We are unconvinced by our data and say that the IV did not affect the DV when it did. Most common when the p value is reduced
What is a variable?
A variable is the phenomenon that changes the depending on the experimental circumstances. It is what varies
What is the independent variable?
IV is manipulated by the researcher to measure the effect of the dependent variable.
What is the dependent variable?
the effect of the IV on the dependent variable is measured. Usually by comparing the results during the experimental condition with results from a control group that has not been subjected to the condition or comparing the results between two experimental groups.
What is a controlled variable?
If the researcher wants to determine a cause-and-effect relationship between IV + DV, they need to control all possible confounding variables. The more that is controlled reduces the ecological validity
What are confounding variables?
situational + participant variables. Any of these might explain differences between the groups, similarly demand characteristics need to be controlled.
What is the experimenter effect?
When the experimenter unconsciously, maybe through body language/tone, gives cues to participants about how to behave. These participant expectations can affect the trustworthiness of the data
What are the methods of controlling confounding variables associated with demand characteristics?
- Single blind technique -> when the participant does not know which group or condition they are allocated to, the experimental group/condition or the control group/condition. This controls participant expectations
- Double blind technique -> when neither the researchers nor the participants know which group or condition the participants are allocated to. This controls the experimenter effect and participant expectations
Probability-based sampling methods
These methods involve randomly selecting participants so that every member of the target population has an equal chance of being chosen. The target population is the group the researcher wants to study. Random selection ensures fairness and reduces bias.
Simple random sampling
to select participants so that each has an equal chance of being selected.
Stratified sampling
This involves dividing your target population into sub-groups and then taking a simple random sample in each sub-group. Has an advantage in that it enables the researcher to present important subgroups of the population . In order to be even more precise, researchers will often use the proportion of participants in the sub-group that represent the proportion of the sub-group in the target population
Cluster sampling
Sampling technique where the entire population is divided into groups or clusters, and a random sample of these clusters is selected. It is typically used when the researcher cannot get a complete list of the members of a population they wish to study, but they can get a complete list of groups of the population. It is also used when a random sample would produce a list of subjects so widely scattered that surveying them would be too expensive
Non-probability based sampling methods
samples are selected based on the subjective judgement of the researcher, rather than random selection. They are more likely to be used in qualitative research because researchers tend to be interested in the details of the sample being studies. While making generalizations from the sample study may be desirable -> it is more often a secondary consideration
Opportunity/convenience sampling
Consists of taking the sample from people are available at the time the study is carried out and fit the criteria the researcher is looking for. Easy in terms of cost + time
Purposive sampling
this is when researchers choose a sample on the basis of those who are most representative of the topic under research or from those with appropriate expertise
