Hypothesis Testing in Psychology Research

Hypothesis testing first starts with theory. Theories are particular assumptions about the way things are. After a theory is formulated, a conceptual hypothesis is created, which is a more specific (than pure theory) prediction about the outcome of something. Next an experimental hypothesis is created. This is where definitions are operationalized so specific matters can be tested. For example, you could operationalize affection as number of hugs and kisses and other related actions. Then you statistically hypothesize in order to measure and test one of two hypotheses: the null, or H0, which represents non-effect (i.e. no difference between samples or populations, or whatever was tested), and an alternate hypothesis, H1.

The alternate hypothesis is that there is a difference, or an effect. It can be that one mean is greater than another, or that they are just not equal. So, the purpose of statistical testing is to test the truth of a theory or part of a theory. In other words, it is a way to look at predictions to see if they are accurate. To do this, researchers test the null hypothesis. We do not test the alternate hypothesis (which is what we think will happen). We do this because we base our testing on falsification logic (i.e., it only takes one example to prove a theory is wrong but conversely you cannot prove that a theory is right without infinite examples, so we look for examples where we are wrong).

The probability associated with a statistical test is assigned to the possibility of the occurrence of Type I error. This is the probability that you will reject the null hypothesis when in fact the null is true and thus should not have been rejected. It is saying there was an effect or a difference when there really was not.

The process of statistical testing can result in probability statements about the theories under consideration but only under certain conditions. Statistical testing and hypothesizing is representative of theory when it is conceptually (verbally and operationally) connected to theory. This means that there has to be a logical and direct association between the statistical probability statements and the theory in order for those statements to represent the overarching theory. This link is forged by the experimental and conceptual hypotheses.

Underlying Assumptions of Cognitive-Behavior Therapy

Cognitive behavior therapies (CBT) all have (or should have) the general underlying model of: Activating Event –> Schemas –> Thoughts –> Behavior/Emotions –> Outcome. In other words, there is a specific and precipitating event that is mentally interpreted, thought about, and acted (or not) upon; all of the steps following the precipitating and activating event lead to a consequence, or outcome. More specifically, our thoughts are really the cause of our behaviors and emotions – our behaviors are internally driven, even in the face of powerful external events. In order for this model to work there are a few basic assumptions that serve as the foundation for cognitive-behavior therapy.Psychotherapy Room

One of these assumptions is that cognitions affect and cause behavior. This goes beyond traditional behavior therapy because cognitions serve as mediating responses between the initial stimuli and behavioral responses. So in effect, it is our cognitions that cause behavior because how we interpret events determines how we react to them. Behavior also can affect cognitions but the general point is that cognitions are not only involved in the behavioral process but necessary to it.

Another assumption is that cognitions are not simply mysterious ephemeral processes – they can be measured, monitored, and altered. Asking people how they think and feel is thus a potentially effective way to understand their behavior. If cognitions can be measured they can also be altered. This means that the way that people think about the world and think about themselves can be changed, which is the goal of CBT when there is maladaptive behavior and cognitions.

As cognitions change, behavior may change. CBT does not ignore the role that changing behaviors (separate from cognitions) has in the therapeutic process but it is important to change cognitions to exact lasting behavioral change. Also, cognitive change is important in cases where situations and external influences on behavior do not, cannot, or will not change.

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