Establishing Cause and Effect - Scientific Causality
Understanding exactly how causation is established in scientific research can help sift It is taking population data and applying it to individual members of the population. and validity, three conditions must be satisfied to demonstrate cause and effect NO OTHER EXPLANATION for the relationship can be present. Concurrent validity (correlation between a new measure and an established measure). This means that the experiment can predict cause and effect ( causation) but a Correlation does not allow us to go beyond the data that is given. Internal validity is the confidence that we can place in the cause and effect construct validity is rarely needed but, for social sciences and psychology, construct.
A correlation can be expressed visually. This is done by drawing a scattergram - that is one can plot the figures for one variable against the figures for the other on a graph. When you draw a scattergram it doesn't matter which variable goes on the x-axis and which goes on the y-axis. Remember, in correlations we are always dealing with paired scores, so the values of the 2 variables taken together will be used to make the diagram.
Decide which variable goes on each axis and then simply put a cross at the point where the 2 values coincide. Some uses of Correlations Prediction If there is a relationship between two variables, we can make predictions about one from another. Validity Concurrent validity correlation between a new measure and an established measure.
Reliability Test-retest reliability are measures consistent. Inter-rater reliability are observers consistent. Theory verification Predictive validity.
The correlation coefficient r indicates the extent to which the pairs of numbers for these two variables lie on a straight line. Values over zero indicate a positive correlation, while values under zero indicate a negative correlation.
Differences between Experiments and Correlations An experiment isolates and manipulates the independent variable to observe its effect on the dependent variable, and controls the environment in order that extraneous variables may be eliminated.
It turns out that in this kind of cyclical situation involving ongoing processes that interact that both may cause and, in turn, be affected by the other. This makes it very hard to establish a causal relationship in this situation.
Covariation of the Cause and Effect What does this mean? Before you can show that you have a causal relationship you have to show that you have some type of relationship. For instance, consider the syllogism: I don't know about you, but sometimes I find it's not easy to think about X's and Y's.
Let's put this same syllogism in program evaluation terms: This provides evidence that the program and outcome are related. Notice, however, that this syllogism doesn't not provide evidence that the program caused the outcome -- perhaps there was some other factor present with the program that caused the outcome, rather than the program.
Establishing Cause & Effect
The relationships described so far are rather simple binary relationships. Sometimes we want to know whether different amounts of the program lead to different amounts of the outcome -- a continuous relationship: It's possible that there is some other variable or factor that is causing the outcome.
This is sometimes referred to as the "third variable" or "missing variable" problem and it's at the heart of the issue of internal validity. What are some of the possible plausible alternative explanations?
In this scenario, the alarm had the effect of you waking up at a certain time. This is what we mean by cause and effect. A cause-effect relationship is a relationship in which one event the cause makes another event happen the effect.
One cause can have several effects. For example, let's say you were conducting an experiment using regular high school students with no athletic ability. The purpose of our experiment is to see if becoming an all-star athlete would increase their attractiveness and popularity ratings among other high school students.
Suppose that your results showed that not only did the students view the all-star athletes as more attractive and popular, but the self-confidence of the athletes also improved.
Social Research Methods - Knowledge Base - Establishing Cause & Effect
Here we see that one cause having the status of an all-star athlete has two effects increased self-confidence and higher attractiveness ratings among other students. Cause-Effect Criteria In order to establish a cause-effect relationship, three criteria must be met. The first criterion is that the cause has to occur before the effect.