PSY302-300852648
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TESTS
Two-sample t-test: between (independent)
Definition: Testing the relationship between a categorical independent variable and a continuous independent variable, in which the categorical independent variable is a between-subjects design with two levels.
Application: This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms.An independent t test was performed and indicated that the manipulation was successful
Two-sample t-test: within (related)
Definition: Testing the relationship between a categorical independent variable and a continuous independent variable, in which the categorical independent variable is a within-subjects design with two levels.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. Two sample t test was used for the comparison of hospitals and employees attitude toward change and comparison of professionas and attitude toward change.
One-Way ANOVA test
Definition: Testing the relationship between a categorical independent variable and a continuous independent variable, in which the categorical independent variable is a between-subjects design with three or more levels.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. One way anova was used to analyze the employees attitudes towards change and management styles of CEO, employees manner of participation in quality studies and comparison of organizational culture.
Two-Way ANOVA test
Definition: Testing the relationship between two categorical independent variable and a continuous independent variable.
Application: This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. Based on 2 levels of self-construal (independent, interdependent) and 2 levels of comparison standard (upward comparison, downward comparison). A two-way ANOVA indicated a significant interaction between self-construal and comparison standard on self-evaluation.
Correlation test
Definition: Testing the relationship between two continuous variables, either of which can be considered the independent or dependent variable.
Application: Researchers tested the realtionship between violent video games and aggresive kids to find a correlation.
Chi-square test
Definition: Testing the relationship between two categorical variables, either of which can be considered the independent or dependent variable.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. Chi square test was used for the comparison of the organizational culture of the hospitals.
Concepts
Standard Score
Definition: a score obtained by using the transformation z=(X-x)/S
Example: http://www.people.vcu.edu/~jldavis/readings/Cialdini%20et%20al%201976%20birg.pdf
Application: This study focused on the tendency to bask in reflected glory by publicly announcing one’s associations with successful others as investigated in three field experiments. By preforming three experiments it was hoped to (a) reliably demonstrate the existence of the phenomenon, (b) establish its generality over experimental contexts and measures, (c) determine a mediating process for its occurrence, and (d) discover some of its limiting conditions and thereby gain further information as to its nature. Z=1.75 in the second experiment.
Confidence Interval
Definition: a range of score values expected to contain the value of mu with a certain level of confidence.
Example: http://jama.ama-assn.org/cgi/content/short/303/9/834?rss=1
Application: This experiment stuied aldosterone antagonists in patients with heart failure. The confidence interval for female sex was CI of 1.01-1.26. so the score is somewhere inbetween the two numbers.
Parametric Test
Definition: a statistical test involving hypotheses that state a relationship about a population parameter.
Application: The purpose of this study was to compare three groups of patients-committed, voluntary and persuaded-admitted to acute psychiatric inpatient care as regards different aspects of satisfaction, treatment and experienced coercion. Data were analysed with nonparametric (Kruskal-Wallis, chi-square)
Nonparametric Test
Definition: a statistical test involving hypotheses that do not state a relationship about a population parameter. Also know as a distribution free test.
Application:The purpose of this study was to compare three groups of patients-committed, voluntary and persuaded-admitted to acute psychiatric inpatient care as regards different aspects of satisfaction, treatment and experienced coercion. Data were analysed with parametric tests (multinominal regression).
Statistically significant difference
Definition: the observed value of the test statistic falls into a rejection region and H0 is rejected.
Application: This study was to find out whether the successful performance on the sex linked tasks was attributed towards luck or skill. The subjects were analyzed based on what attributions they presented towards the stimulus person performing sex linked tasked. Subjects then attributed whether the performance was attributed towards luck or skill.The sex of stimulus and sex of task interacion was significant (p<.01).
Nonsignificant difference
Definition: the observed value of the test statistic does not fall into a rejection region and the null hypothesis is not rejected.
Example: http://www.people.vcu.edu/~jldavis/readings/Cialdini%20et%20al%201976%20birg.pdf
Application: This study focused on the tendency to bask in reflected glory by publicly announcing one’s associations with successful others as investigated in three field experiments. By preforming three experiments it was hoped to (a) reliably demonstrate the existence of the phenomenon, (b) establish its generality over experimental contexts and measures, (c) determine a mediating process for its occurrence, and (d) discover some of its limiting conditions and thereby gain further information as to its nature. There were no significant sex effects in the data in the second experiment.
Between-subjects Design, with two groups
Definition: an experiment in which two groups are created.
Application: This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. The experiment employed a 2 × 2 between-subjects design based on 2 levels of self-construal (independent, interdependent) and 2 levels of comparison standard (upward comparison, downward comparison).
Between-subjects Design, with three or more groups
Definition: an experiment in which three or more groups are created.
Application: This study was to find out whether the successful performance on the sex linked tasks was attributed towards luck or skill. The subjects were analyzed based on what attributions they presented towards the stimulus person performing sex linked tasked. Subjects then attributed whether the performance was attributed towards luck or skill. This is a 2x2x2 factorial between subjects design. Three IV's with two levels. There are three IV's sex of stimulus(A), sex of task(B), and sex of subject(C). also being tested are AxB, AxC, BxC, AxBxC.
Random sampling
Definition: a sampling method in which individuals are selected so that each member of the population has an equal chance of being selected for the sample, and the selection of one member is independent of any other member of the population.
Example: http://www.people.vcu.edu/~jldavis/readings/Cialdini%20et%20al%201976%20birg.pdf
Application: This study focused on the tendency to bask in reflected glory by publicly announcing one’s associations with successful others as investigated in three field experiments. By preforming three experiments it was hoped to (a) reliably demonstrate the existence of the phenomenon, (b) establish its generality over experimental contexts and measures, (c) determine a mediating process for its occurrence, and (d) discover some of its limiting conditions and thereby gain further information as to its nature. 173 subjects were randomly sampled from a school directory for experiment two.
Random Assignment
Definition: a method of assigning subjects to treatment groups so that any individual selected for the experiment has an equal probability of assignment to any of the groups and the assignment of one subject to a group does not affect that assignment of any other individual to that same group.
Example: http://www.urban.org/publications/411350.html
Application: This study randomly assigned there subjects. subjects had equal chance of going in any groups.
Independent Variable
Definition: a variable manipulated in an experiment to determine its effect on the dependent variable.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. Independent variables were hospital, organizational culture, job, CEO management style, and participatino style to quality studies.
Levels of the Independent Variable
Definition: one value of the independent variable. to be a variable, an independent variable must take on at least two different levels.
Application:This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. The experiment employed a 2 × 2 between-subjects design based on 2 levels of self-construal (independent, interdependent) and 2 levels of comparison standard (upward comparison, downward comparison).
Confounds
Definition: an extraneous variable that is covarying with the independent variable, potentially masking the true effects of the independent variable on the dependent variable.
Application: one confound could be the temp when the aggressive behavior happened. the hotter it is the more disconfort you feel. therefore making you more aggressive.
Dependent Variable
Definition: the variable in an experiment that depends on the independent variable. in most instances the dependent variable is some measure of a behavior.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. The dependent variables were organizational culture and attitude toward change.
Within-subjects Design, with two groups
Definition: within-subjects designs are designs in which the same variable is measured repeatedly on the same participant under different task conditions.
Example: http://web.mst.edu/~psyworld/mixed_designs.htm
Application:This design would consist of one within subject variable (test), with two levels (pre and post), and one between subjects variable (therapy), with two levels (traditional and cognitive)
Within-subjects Design, with three or more groups
Definition: within-subjects designs are designs in which the same variable is measured repeatedly on the same participant under different task conditions.
Application:The present study tried to replicate the findings under stringently controlled conditions. 32 Ss (mean age 22 yrs) who smoked at least 5 cigarettes a day for 2 yrs participated in a 2 x 2 x 6 within-subject design. three groups two with two levels and one with six levels.
Main effect
Definition: the mean of all subjects given one level of an IV, ignoring the classification by the other IV in a factorial design.
Application: This study was to find out whether the successful performance on the sex linked tasks was attributed towards luck or skill. The subjects were analyzed based on what attributions they presented towards the stimulus person performing sex linked tasked. Subjects then attributed whether the performance was attributed towards luck or skill. The overall main effect of sex of stimulus person indicated that independent of task males were rated as more skillful than females (p<.05).
Interaction
Definition: a situation in a factorial design in which the effect of one independent variable depends on the level of the other independent variable with which it is combined.
Application: This study was to find out whether the successful performance on the sex linked tasks was attributed towards luck or skill. The subjects were analyzed based on what attributions they presented towards the stimulus person performing sex linked tasked. Subjects then attributed whether the performance was attributed towards luck or skill. There is an interaction of sex of actor and sex of task. the sex of stimulus and sex of task interacion was significant (p<.01).
Strength of Effect (Eta squared)
Definition: the measure of effect size for use in ANOVA
Application:This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. There was a significant main effect of self construal with a eta squared of .08
Scatterplot
Definition: a plot of a bivariate distribution in which the X variable is plotted on the horizontal axis and they Y variable is plotted on the vertical axis.
Example: http://staff.argyll.epsb.ca/jreed/math9/strand4/scatterplot1.gif
Application: Dots are plotted on a graph with means of temp on the vertical axis and evelation on the horizontal axis.
Positive relationship
Definition: a relationship between two variables in which, as the value of one variable increases the value of the other variable tends to increase also.
Example: http://www.jamaicaobserver.com/news/Ganja-smoking-linked-to-psychosis_7462461
Application: This experiment studied the relationship between ganja smoking and psychosis. The longer the duration since first cannabis use, the higher the risk of the adverse outcomes.
Negative relationship
Definition: a relationship between two variables in which, as the value of one variable increases, the value of the other variable tends to decrease.
Example: http://staff.argyll.epsb.ca/jreed/math9/strand4/scatterplot1.gif
Application: there tends to be a negative relationship between mean annual temp and evelation. as the evelation increases the mean annual temp decreases.
No relationship
Definition: there is no consistant relationship between variables.
Application: This study was to test for a relationship between vaccines and autism. No association between measles vaccination and ASD was shown. The variables did not show any relationship.
Linear relationship
Definition: a relationship between two variables tht can be described by a straight line.
Example: http://www.jamaicaobserver.com/news/Ganja-smoking-linked-to-psychosis_7462461
Application:This experiment studied the relationship between ganja smoking and psychosis. There were significant linear trends between the exposure variable and all three psychosis-related measures.
Curvilinear relationship
Definition: A line appearing as a curve; nonlinear.
Example: http://www.realclearpolitics.com/horseraceblog/Theorized%20Relationship.gif
Application: This study was to show the relationship between clintons performance and partisanship of district. There is a curvilinear relationship between clintons performance and partisanship of district. Small with defeat and heavy rep and defeat and heavy dem. High when victory and swing.
Coefficient of Determination
Definition: r^2 The squared value of r, provides an analogous measure of the strength of association between X and Y.
Application:This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. r=-.17 and r^2 = .03
Correlation does not equal causation
Definition: correlation does not equal causation, there is a possibility that a third vairable could have contributed to the results.
Application: In the correlation of violent video games and aggressive kids a third variable could be if there was domestic violence in the household. That could also attribute to the child having aggressive behavior.
Extra-Credit (3 points each)
Normal Distribution
Definition: a theoretical mathematical distribution that specifies the relative frequency of a set of scores in a population.
Example: http://www.mathsisfun.com/data/images/standard-normal-distribution.gif
Application: Assuming normality a normal distribution is symmetrical, asymptotic and continuous.
Symmetrical
Definition: mean, mode and median are the same.
Example: http://www.mathsisfun.com/data/images/standard-normal-distribution.gif
Application: a normal distribution bell curve is symmetrical. if folded in the middle both sides will be the same.
Asymptotic
Definition: the tail regions approach the ase line but never touch it.
Example: http://www.mathsisfun.com/data/images/standard-normal-distribution.gif
Application: The ends of a normal distribtion will never touch the bottom of the graph. The ends extend to negitive infinity and positive infinity.
Continuous
Definition: Of or relating to a line or curve that extends without a break or irregularity.
Example: http://www.mathsisfun.com/data/images/standard-normal-distribution.gif
Application:the ends of a normal distribtion will never touch the bottom of the graph. The ends extend to negitive infinity and positive infinity.
Sampling Error
Definition: the amount by which a sample mean differs from the population mean.
Example: http://news.yahoo.com/s/rasmussen/20100305/pl_rasmussen/congresshealthcare20100305_1
Application:The margin of sampling error for the survey is +/- 3 percentage points with a 95% level of confidence.
Null Hypothesis
Definition: a statement of a condition that a scientist tentatively holds to be true about a population. the null hypothesis is the hypothesis tested by a statistical test.
Example: http://www.referenceforbusiness.com/management/Gr-Int/Hypothesis-Testing.html
Application: Ho = 20 years. If true it has to equal 20.
Alternative Hypothesis
Definition: a statement of what must be true if the null hypothesis for a statistical test is false.
Example: http://www.referenceforbusiness.com/management/Gr-Int/Hypothesis-Testing.html
Application: H1 does not equal 20. True if hull hypothesis is rejected.
Significance level
Definition: a probability value that provides the criterion for rejecting a null hypothesis in a statistical test.
Example: http://www.referenceforbusiness.com/management/Gr-Int/Hypothesis-Testing.html
Application: In this example the significant level is .05
Two-tailed test
Definition: a statistical test using rejection regions in both tails of the sampling distribution of the test statistic.
Example: http://www.people.vcu.edu/~jldavis/readings/Cialdini%20et%20al%201976%20birg.pdf
Application: This study focused on the tendency to bask in reflected glory by publicly announcing one’s associations with successful others as investigated in three field experiments. By preforming three experiments it was hoped to (a) reliably demonstrate the existence of the phenomenon, (b) establish its generality over experimental contexts and measures, (c) determine a mediating process for its occurrence, and (d) discover some of its limiting conditions and thereby gain further information as to its nature. There was a two tailed Z test in the second experiment were the rejecion region is possible in both ends.
One-tailed test
Definition: a statistical test employing a rejection region in only one tail of the sampling distribution of the test statistic.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. Anova was used in this study and anova uses one tailed test.
Degrees of Freedom
Definition: the number of scores free to vary when calculating a statistic.
Application: This study was to find out whether the successful performance on the sex linked tasks was attributed towards luck or skill. The subjects were analyzed based on what attributions they presented towards the stimulus person performing sex linked tasked. Subjects then attributed whether the performance was attributed towards luck or skill. The df's are: sex of stimulus =1, sex of task =1,sex of subject =1, AxB =1,AxC =1, BxC =1, AxBxC =1, Within =122
Type I Error
Definition: the error in statistical decision making that occurs if the null hypothesis is rejected when actually it is true of the population.
Example: http://www.telegraph.co.uk/news/uknews/2484897/Doctors-fail-to-spot-toddlers-broken-collar-bone.html
Application: The doctor failed to diagnose the toddler with a broken collar bone. when it was really broken.
Type II Error
Definition: the error in statistical decision making that occurs if H0 is not rejected when it is false and the alternative hypothesis (H1) is true.
Example: http://www.newsvine.com/false-diagnosis
Application: doctor diagnosed man wrong. Doctor told man he had a sort time to live when he really didnt have any seriouse illness.
Power
Definition: the probability of rejection H0 when H0 is false and H1 is true. the power of a statistical test is given by 1-B.
Application: This study investigated the role of self construal as a moderator of the social comparison effects in authentic classrooms. The power of the anova was .001
Pairwise comparisons
Definition: statistical comparisons involving two means.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. The tukey HSD showed a significant differences between power culture and role, cometition, and copperation culture, and betweem competition culture and cooperation culture score averages. Comparing power culture M=53.77& Role culture M=63.4,competition culture M=69.68 & cooperation culture M=73.9,role culture & cooperation culture, Role culture & cometition culture, power culture & cooperation culture, Power culture & competition culture.
Post-hoc comparisons
Definition: statistical tests that make all possible pairwise comparisons after a statistically significant Fobs has occurred for the overall analysis of variance.
Application:The purpose of this study was to define organizational culture in hospitals that have received quality certificates and to identify attitudes of health care a personnel toward change. The tukey HSD showed a significant differences between power culture and role, cometition, and copperation culture, and betweem competition culture and cooperation culture score averages.Comparing power culture M=53.77& Role culture M=63.4,competition culture M=69.68 & cooperation culture M=73.9,role culture & cooperation culture, Role culture & cometition culture, power culture & cooperation culture, Power culture & competition culture.
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