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Inferential statistics are based on the laws of ________.
probability

Inferential statistics provide a means for _________ about a population, given data from a sample.
drawing conclusions

The tendency for statistics to fluctuate from one sample to another.
sampling error

A theoretical (rather than actual) distribution b/c no one draws consecutive samples from a population and plots their means.
Sampling distribution

The SD of a sampling distribution of the mean.
Standard error of the mean (SEM)

The word ______ signifies that the various means in the sampling distribution have some error as estimates of the population mean.
error

The smaller the SEM, the _______ the means are as estimates of the population value.
 more accurate
 (less variable)

___________ is used to estimate a parameter  for example, a mean, a proportion, or a mean difference b/w two groups.
Parameter estimation

With interval estimation, researchers construct a _________ around the estimate.
Confidence interval (CI)

What are confidence limits?
Upper and lower limits of confidence interval

A ________ distribution is the probability distribution of the number of "successes" in a sequence of independent yes/no trials, each of which yields "success" with a specified probability.
binomial

What is the best way to get representative samples?
probability samples

To estimate population parameters, it is advisable to use _______ samples.
representative

Researchers use inferential statistics to estimate _______ ________________ from _________ statistics.
 population parameters
 sample

Inferential statistics provide a framework for making _______ judgments about the _______ of sample estimates.

The ________ of statistical calculations depends on the extent to which results from a sample are similar to what you would have obtained had you randomly selected people from the population.
validity

_________ involves calculating a single descriptive statistic to estimate the population parameter.
point estimation

_____ estimates convey NO info about margin of error so inferences about the accuracy of the parameter estimate cannot objectively be made.
point

________ estimation is useful because it indicates a RANGE of values within which the parameter has a specified probability of lying.
interval

With _____ estimation, researchers construct a confidence interval (CI) around the estimate.
interval

Constructing a CI around a sample mean establishes a range of values for the population value as well as the probability of what?
being right! (the estimate is made with a certain degree of confidence)

THe CI is rarely ________ around a sample proportion.
symmetric

The ______ of the CI depends on the value of the proportion AND the sample size.
width

The larger the sample size, the _______ the CI.
smaller

The CI for a proportion never extends below ____ or above _____.

CI convey importan info about the _______ of the estimate.
precision

Hypothesis testing is based on _______ inference.
negative

Researchers make a ______ error by rejecting a null hypothesis that is actually true.
Type I

False negative conclusion.
Type II error

A ____ error might allow an ineffective drug to come onto the market.
Type I

A ________ error might prevent an effective drug from coming onto the market.
Type II

Researchers control the risk of a _______ error by selecting a level of significance.
Type I

A level of significance signifies the probability of ___________ a true null hypothesis.
incorrectly projecting

The two most frequently used significance levels are ___ and _____ and are referred to as ________

Increasing sample size will reduce the risk of a ______ error.
Type II

By selecting a significance level, researchers establish a ________.
decision rule

The decision rule is to reject the null hypothesis if the test statistic falls at or beyond the limits that establish a _________ on an applicable theoretical distribution and to accept the null hypothesis otherwise.
critical region

The ________ indicates whether the null hypothesis is IMPROBABLE given the results.
critical region

In onetailed tests, the critical region of improbable values is in only one tail of the distribution  the tail corresponding to what?
the direction of the hypothesis

Easier or harder to reject null hypothesis with a onetailed test?
easier

Two classes of statistical tests.
Parametric and nonparametric

_______ tests involve estimation of a parameter, require measurements on at least an interval scale, and involve several assumptions like variables are normally distributed.
Parametric

________ tests do NOT estimate parameters and involve less restrictive assumptions about the shape of the distribution.
nonparametric

_______ tests are more powerful than ________ tests.
parametric; nonparametric

When comparisons involve different people (men vs women), the study uses a ______ design, and the statistical test is a test for _________.
 betweensubjects
 independent groups

In ________ designs, comparisons are not independent b/c the same people are used in all conditions, and the statistical tests are tests for ________.
 withinsubjects;
 dependent groups

____________ refers to the number of observations free to vary about a parameter.
degrees of freedom

If the absolute value of the test statistic is ________ than the tabled value, the results are statistically significant.
larger

Any computed probability greater than ______ indicates non significance.
.05

A _______ can be used when there are two independent groups and when the sample is dependent.
ttest

When there are multiple dependent variables, the risk of a _______ error increases.
Type I

Researchers sometimes apply a __________ when they run multiple tests to establish a more conservative alpha level.
Bonferroni correction

The Bonferroni correction tends to increase the risk of ________ error.
Type II.

Incorrectly concluding there is no statistical association when in fact there is one.
Type II error

______________ can be constructed around the difference b/w two means, and the results provide info about BOTH statistical sig and precision of estimated difference.
Confidence intervals

________ is richer and more useful in clinical applications than p values.
CI

A _______ is computed from pretest and posttest data.
ttest

The ______ test involves assigning ranks to the two groups of scores.
MannWhitney U

The _________ test involves taking the difference b/w paired scores and ranking the absolute difference.
Wilcoxon signedrank

________ is the parametric procedure for testing differences b/w means when there are three or more groups.
Analysis of Variance (ANOVA)

The statistic computed in ANOVA.
Fratio

ANOVA decomposes total _________ in a ______ variable.

Variation between groups is contrasted with variation within groups to get _______.
an Fratio

When differences b/w groups are large relative to variation within groups, the probability is _______ that the independent variable is related to or has caused group differences.
high

The ___________is the sum of sum of squared deviations of individual group means from the overal grand mean for all participants.
sum of squares between groups

The ______ is the sum of the squared diviations of each individual score from its OWN group mean.
sum of squares within groups

The function of __________ is to isolate the differences b/w group means that are responsible for rejecting the overall ANOVA null hypothesis.
multiple comparison procedures (post hoc tests)

In multiple comparison procedures, why is it NOT appropriate to use a series of ttests?
b/c this would increse the risk of a Type I error

__________ is used to test the relationship b/w one categorical independent variable and a continuous dependent variable.
Oneway ANOVA

__________ concerns whether the effect of one independent variable is consistent for all levels of a second independent variable.
Interaction

________ ANOVA is used when thre are 3 or more measures of the SAME dependent variable for each participant.
Repeatedmeasures

Sum of squarestreatments is the same as the sum of squaresbetween in regular ANOVA and represents the effect of the ________ variable.
independent

The sum of squareserror is similar to the sum of squareswithin in regular ANOVA and both represent variations associated with _______.
random fluctuations

The sum of squares_____ has no counterpart in a simple ANOVA. Why?
 subjects
 b/c those being compared are not the same people

The SSsubjects term captures _______.
individual differences

_____ ANOVA yields a more sensitive test of the relationship b/w the IV and DV than ________ ANOVA.

What is removed from the denominator in computing the Fstatistic?
variability attributable to individual differences

The ______ test is a generalized version of teh MannWhitney U test.
KruskalWallis

The __________ test is based on assigning ranks to the scores of various groups.
KruskalWallis or MannWhitney U

The ________ test is used when the number of groups is greater than two and a oneway test for indepenent samples is desired.
KruskalWallis or MannWhitney U

The ________ test is for ANOVA by ranks .
Friedman

The _________ test is used to test hypotheses about group differences in proportions, as when a contingency table has been created.
chisquare

The _______ test enables us to decide whether a difference in propertions of a certain magnitude is likely to reflect a real tx effect or only chance fluctuations.
chisquare

_________ are the cell frequencies that would be found if there was no relationship b/w the two variables.
Expected frequencies

The _______ statistic is computed by summarizing differences b/w observed and expected frequencies for each cell.
chisquare

When is a chisquare test not appropriate?
 when sample size is small (30 or less), OR
 when there are cells with small frequencies (5 or fewer)

___________ test should be used to test the significance of differences in proportions.
Fisher's exact

When the proportions being compared (pretestposttest design is used to compare changes in proportions on a dichotomous variable) are from two paired groups the appropriate test is ________.
McNemar's

What is the correlation coefficient calculated when two variables are measured on at least the interval scale?
Pearson's r

Pearson's r summarizes the _______ and ________ of a relationship b/w two variables.

Pearson's r can be used both _____group and ______group situations.

If test scores are obtained before and after an event, the correlation b/w the two scores is a ______group situation.
within

Pearson's r is a ________statistic.
parametric

When the assumptions for a parametric test are violated, or when the data are ordinal level, the appropriate coefficient of correlation is ____________.
 Spearman's rho OR
 Kendall's tau

The chisquare statistic is computed by comparing ______ frequencies with ______ frequencies.

