Psych 243 1st EditionExam # 1 Study Guide Lectures: 1 - 5Lecture 1 (1/27/15)Psych Research has 2 elements:- Research methods: formulate questions & collect data (architect)- Statistics: A set of methods & rules for organizing, summarizing & interpreting data (contractor)o Descriptive: Organizing, summarizing & looking for relationships in a sample or population Relationship: when a change in one variable leads to a systematic change in another variableo Inferential: techniques based on probability that tell us whether we can generalize beyond our sample to the population Population: Entire set of individuals that you purport to study Sample: Relatively small subset of scores or individuals that you have available- Should be randomly selected & representative of a population Lecture 2 (1/29/15) Scientists use statistics to study a mathematic relationship between one or more variables- 2 Ways to study variables:o Experiment: researcher manipulates variable & measures effect on the variable, while keeping everything else constant. Randomly assigns subjects to groups Dependent Variable: behavior measured by experimenter Independent Variable: manipulated by experimenter to see if it affects the behavior have different conditions (specific amounts of IV) Quasi-Independent variable: variables that can’t be randomly assigned (age, race, gender…)o Correlational study: measures 2 things & determine whether there is a relationship between them Correlation does not equal causation 3rd variable problem: there may be some other variable not measured by the experimenter that cause both outcomes Even if link is causal, direction of causation cannot easily be determined:even if there is a causal link, often you don’t know which variable causes which Lecture 3 (2/3/15)Measurement Scales- Nominal= nameo Has no amount, differ only in kindo Gender, religion, political affiliation- Ordinal= ordero Ranking  difference between ranks does not mattero Sports standings, class rankings- Intervalo Ordered categories of the same size no true zeroo Temperature or Psychological scales- Ratioo Real 0 & quantitativeo Height, weight, exam scoreFrequency- N: Total number of scores- F: frequency; the number of times a particular value of your variable occurs- Rf: Relative frequency; proportion of the total N made up by a score’s simple frequency- Cf: Cumulative frequency; sum of all the frequencies of all the scores at or below a particular score- Rcf: relative cumulative frequency; sum of all the relative frequencies at or below a particular score- Displaying frequency:o Histogram/frequency polygon interval/ratioo Bar graph nominal/ordinalo Pie graph sometimes nominalLecture 4 (2/5/15)- Normal Distributiono 1 peak unimodalo Symmetrical- Positively Skewedo Few extremely high scores raise the tails on the righto Not balanced with corresponding low scores- Negatively Skewedo Few extremely low scores are raising the tail on the lefto Not balanced with corresponding high scores- Bimodal Distributiono Two high frequency peaks - Mediano Exactly half the scores are lower than the median & exactly half the scores are higher - Meano Mathematical center of distribution- Modeo Scores that occur most frequently in sampleLecture 5 (2/10/15)- Deviation from the mean: subtract the mean from the scoreo Positive deviation: higher than the meano Negative deviation: lower than the mean- Steps to find standard deviation (formulas are given):o Find the No Find the meano Find the simple deviation by subtracting the mean from each scoreo Square each simple deviationo Divide by N varianceo Take the square root to find x- Use the (N-1) formula when trying to estimate standard deviation of a