Students should be able to describe and differentiate between longitudinal and cross sectional designs o Longitudinal makes observations of one group over time observe 20 y o and check on them every 20 years o Cross sectional makes observations of many groups at once observe a group of 20 y o 40 y o 60 y o at one time Students should be able to describe and differentiate between idiographic causal explanation and nomothetic causal explanations and give an example of each o Nomothetic is when there is a correlation between the independent and dependent variables a bunch of events Ex explaining adults propensities to commit crimes find that presence of childhood abuse correlates to more crime o Idiographic is a sequence of events that lead to a particular outcome for a specific individual one event Ex explaining why the Civil War happened not trying to explain why all wars happen just this one particular war Students should be able to explain what an extraneous variable and spurious relationship are o A spurious relationship is a relationship between two occurrences that seem to have relationship but don t A third unforeseen variable extraneous variable affects the other two variables and leads one to conclude that the other two are casually linked Ex This example illustrates a spurious relationship as a city manager has accumulated data from 100 fires the number of fire trucks dispatched and the amount in damaged caused by these fires The city manager notices a strong correlation between the number of trucks dispatched and the amount in fire damage He concludes if fewer trucks were dispatched there will be less fire damage While this is obviously incorrect there is a third variable that was failed to take into account which is the size of the fire The amount of the fire trucks dispatched was caused by a variation of the size of the fire This is spurious relationship or false indication of causality Students should be able to differentiate between correlation and causation and explain the relationship between these concepts o Correlation a mutual relationship or connection between two or more things o Causation the action of causing something o Correlation does not imply causation Students should be able to identify the three criteria necessary to establish a nomothetic causal relationship KNOW THESE o 1 Empirical association variables have to be correlated political orientation and views on marijuana o 2 Cause takes place before effect o 3 Variables are non spurious effect cannot be explained in terms of a third variable Students should be able to identify and differentiate between the four types of validity considered when examining a research design Internal External Measurement Statistical o Internal validity also called causality examines whether the observed change in a dependent variable is indeed caused by a corresponding change in hypothesized independent variable and not by extraneous variables o External validity generalizability whether the observed associations can be generalized from the sample to the population or to other people organizations contexts or time o Measurement examines how well a given measurement scale is measuring the theoretical construct that it is expected to measure o Statistical examines the extent to which conclusions derived using a statistical procedure is valid Students should be able to describe the role of Time Sequencing in Research Designs o The timing of events in a study common usage includes corss sectional study longitudinal cohorts and time between treatments Students should be able to explain the importance of Treatment Fidelity in research designs and recognize examples of violations of this principle o Treatment fidelity is the treatment administered correctly and o It is important to get the most accurate results o A violation would be skipping a dosage of a medication in an consistently experimental trial Students should be able to explain the importance of handling missing Data and Power Analysis in a Research Design o Missing data can be replaced by a process called imputation where the data of that particular question is averaged out and that is what is put in the place of the missing value Can skew the results o Power whether or not you have enough people to make an analysis Students should be able to identify and explain the differences between major statistical approaches Frequentist vs Bayesian Inferential vs Descriptive Point Estimates vs Confidence Intervals Parametric vs Non Parametric o Frequentist focuses on drawing statistical inferences based on frequencies or proportions within the observed data and hypothesized prior to distributions comparing frequency and observed data to prior distribution o Bayesian focuses on dynamically updating estimates of population parameters by integrating new data with previously held beliefs constantly updating estimates about population parameters o Descriptive focus on characterizing the statistical trials of a data set mean mode SD o Inferential statistics focus on drawing conclusions about data and the populations they are drawn from o Point estimates provide a single number estimate such as a mean of a statistic or parameter Do not describe variability of the statistic or parameter Easier to use when making a quick summary of data o Confidence interval provide a broader estimate of statistic or parameter Provide richer information about the distribution of a parameter Instead of mean is 38 use about 95 of the scores fall between 37 and 38 o Parametric assume the data comes from a probability distribution Data from these are ordinal interval or ratio Most statistics are parametric statistics o Non parametric do not assume the data comes from a probability distribution Data can be nominal or ordinal Not used in a lot of research Most common is the x2 test Students should be able to identify the three common measures of central tendency and be able to calculate these when given a simple data set ex 1 2 2 3 o Estimate of center of distribution Mean the average of all values sum of all scores number of scores mean Median the middle value of a range of values put data in ascending order and find middle value Mode the most frequent value of a range of values Students should be able to identify symmetrical and skewed distributions and explain how these affect measures of central tendency o Symmetrical mean median and mode should be roughly equal o Skewed mean median and mode are not