Research Exam

 Stem and Leaf Plot Shows the frequency of happenings in statsxxxxxxxxxxxxxxxxxxxxxx Histogram Frequency chart shown as bars Bell Bell Curve A chart showing the standard deviation from the normed center of the plotting Nominal Scale Least PrecisePuts Variables into CategoriesLike race, socio-economic Chi Squared Designed to measure the significance between 2 variables Ordinal 2nd Least Precise measurementCategorizes by magnitude highest to lowestClass rankNo real detail about why the grades are the way they are, just that they are Interval The Most Used for of Measurement in EducationCatergories by magnitude and understanding the why of the intervals in betweenNo Absoulte Zero...there will always be somethingUses Pearson r for correlationBe wary of using this to make predictions...not always cause & effect Ratio Most PreciseCategories of data showing magnitudeIntervals are the same size and there is true zeroData can be manipulated Descriptive Statistics Looking at the numbers and doing things like:AveragesMedianMode Correlation is not Causation Cummulative Percentage ChartSpearman is all about the rank order of things Central Tendency Single Value that is considered the most typical...a norm at which to determin standard deviation Validity Using the right tool to measure correctly Content Validity- the items on the instrument refelct the content Construct Validity- the extent to which a higher order construct is represented in a study (Help Seeking, stress, dyslexia...etc.) Reliability Having reliable scores Having temporal stability- stability over time Angoff Method- standard setting Internal Validity The ability to infer that a causal relationship exists between 2 variables External Validity The extent to which the study can be generalized and applied across populations Errors of Measurement Standard Deviations from the norm Always going to have errors in samples, mathematical The small the standard deviation the more accurate the measure Standard Error of Measurement The standard deviation of a sample population Null Hypothesis A statement about a population parameter some condition concerning the pop. parameter is true. prediction of no difference in a study when a new treatment is given Rejecting the Null Hypothesis When there is a relationship between populations due to the given treatment you reject the null hypothesis Accepting the Null Hypothesis Means you are admitting that there is no relationship between populations given the treatment Inferential Statistics Inferring information from a sample to a larger population Types 0f Samples Random SampleSampling IntervalStratified SampleCluster SampleConvenience SamplingQuota SamplingPurposive Sampling (Judgemental)Snowball Sampling Type One Error To say it had an effect, but it really didn't have one Type 2 Error To say the treatment did not have an effect when it really did Power The larger the sample size the more power a test has...it is more sensitive. The Bigger the sample size the better...less likely to have a Null hypothesis Effect Size Indicator A statistical measure to show strength of a relationship Practical Significance A conclusion made when a relationship is strong enough to be of practical importance t Test Used to compare 2 group means Used to determine if the difference between sample populations was created merely by chance errors or really because of the treatment ANOVA ANOVA is used to compare one or more group means Can compare more than 2 groups Gives a p value Scientific Method QuestionResearchHypothesisTestAnalyzeTest AgainReport Alternate Hypothesis-Example Male and Female population's means on SAT tests are different Null Hypothesis- Example Male and Female population means on not different on the SAT Pearson Product Moment Correlation Shows a correlation between 2 ideas Higher tuition correlates to lower enrollment Tested with the Pearson r Authorpml16189 ID2017 Card SetResearch Exam DescriptionResearch Final Exam Updated2009-12-01T19:53:52Z Show Answers