chapter 14

what is a chi-square goodness-of fit test used to determine

how well a set of observed frequencies fits with what was expected

what does NHST indicate

if an effect exists in a population

a statement about a population parameter, such as the population mean, that is assumed to be true but contradicts the research hypothesis; we assume we are wrong

null hypothesis

a significance test that is used to test hypotheses about parameters in a population in which the data in the population are normally distributed and measured on an interval or ratio scale of measurement is called

parametric test

significance tests that are used to test hypotheses about parameters in a population in which the data in the population are normally distributed and measured on an interval or ratio scale of measurement

parametric tests

a sample statistic that is used to estimate a population parameter

point estimate

the probability of rejecting a false null. specifically, the probability that we will detect an effect if an effect actually exists in a population

power

what is the decision for a null hypothesis test when the likelihood of obtaining a sample out come is less than .5% if null were true

reject the null

A researcher reports a 95% CI 2.30, 2.50. If the null hypothesis were that the mean in the populaiton equals 2.00, then what would the decision have been for a significance test at a .05 level of significance?

reject the null because 2.00 is not contained in the confidence level

if the null is rejected what do we reach

significance

describes a decision made concerning a value stated in the null.

significance, statistical significance

what coefficients are mathematically equivalent to the Pearson correlation coefficient

spearman, point-biserial, and phi correlation coefficients

in Cohen's d, the bigger the value of d....

the large the effect in the population

effect size indicates

the size of an effect in a population

what can the value of the test statistic be used for

to make a decision regarding the null

when the p value is less than .05

we reject the null and state that an effect or difference reached significance

what are parametric tests used for

when data in the population are normally distributed and measured on an interval or ratio scale

what do we test in the null hypothesis

whether the value stated in the null hypothesis is likely to be true

standard rules for identifying small, medium and large effects based on typical findings in behavioral research

Cohen's conventions/ effect size conventions

a measure of effect size in terms of the number of SD that mean scores shifted above or below the population mean stated by the null.

Cohen's d

what is the corresponding effect size measure for correlation and regression

R squared

what type of hypothesis test can use Cohen's d as an estimate of effect size

one sample t test

what do we use inferential statistics for

to make decisions about characteristics in a population based on data measured in a sample

if the likelihood of obtaining a sample outcome is greater than 5% if the null were true....

we retain null because the sample outcome would be likely to occur if the null were true

what are nonparametric tests used to

analyze nominal and ordinal data from populations with any type of distribution

its value represents the proportion of variance in a DV that can be explained by the levels of a factor

anovas

the significance and effect size of an outcome can be determined based on the

confidence interval identified at a specified level of confidence

the upper and lower boundaries of a confidence interval given within a specified level of confidence

confidence limits

a statistical procedure in which a sample statistic is used to estimate that value of an unknown population parameter.

estimation

the probability or likelihood that an interval estimate will contain the value of an unknown population parameter

level of confidence

a criterion of judgment upon which a decision is made regarding the value stated in a null hypothesis. the criterion is based on the probability of obtaining a statistic measured in a sample if the value stated in the null hypothesis were true

level of significance, significance level

inferential statistics are procedures used to

make decisions about characteristics in a population based on data measured in a sample

a point estimate is generally the ____ of a confidence interval

midpoint

a researcher evaluates preferences for each of three advertisements aimed at children. he asks 60 parents to choose their favorite ad and records their choice. what type of analysis is appropriate for this research design

chi square goodness of fit test

a statistical procedure used to determine whether observed frequencies at each level of one categorical variable are similar to or different from frequencies expected

chi-square goddness-of fit test

a statistical procedure used to determine whether frequencies observed at the combination of levels of two categorical variables are similar to or different from frequencies expected

chi-square test for independence

a measure of proportion of variance used to describe effect size for data analyzed using a correlation coefficient or regression. mathematically equivalent to eta squared

coefficient of determination [r squared]

a mean difference or discrepancy between what was observed in a sample and what was expected to be observed in the population

effect

a measure of effect size in terms of the proportion or percent of variability in a DV that can be explained or accounted for by the levels of a factor or treatment

proportion of variance

its value represents the number of SD's that scores shift or fall above or below a value stated in a null hypothesis

t tests/Cohen's d

mathematical formula that allows researchers to determine the likelihood of obtaining sample outcomes if the null were true.

test statistic

its value represents the proportion of variance in values of one factor that can be explained by changes in the values of a second factor

correlation and regression/ chi square test for independence

a measure of proportion of variance that is used as an estimate of effect size for the chi square test for independence

cramer's v

corresponding effect size measure for chi square test for indpendence

cramer's v

statistical measure of the size or magnitude of an observed effect in a population, which allows researchers to describe how far scores shifted in a population, or the percent of variance in a dependent variable that can be explained by the levels of a factor

effect size

what is cramer's v used to estimate

effect size when data are analyzed using the chi square test for independence

procedures that allow researchers to infer or generalize observations made with samples to the larger populations from which they were selected

inferential statistics

the interval or range of possible values within which an unknown population parameter is likely to be contained

interval estimate[confidence interval]

what is the corresponding effect size measure for ANOVAs

n squared

a signifance test that is used to test hypotheses about data that can have any type of distribution and to analyze data on a nominal or ordinal scale of measurement is called

nonparametric test

significance tests that are used to test hypotheses about data that can have any type of distribution and to analyze data on a nominal or ordinal scale of measurement

nonparametric tests

how can a confidence interval be described in terms

of the precision and certainty of an interval estimate

what kind of tests for Cohen's d

one sample, two-independent sample, and related sample t tests

the probability of obtaining a sample outcome if the null were true

p value

to apply NHST, we state a null hypothesis, and then set a criterion upon which we will decide to

retain or reject the null

what is the p value compared to

the level of significance to make a decision about a null

what can a chi square test for independence be used for

to determine if frequencies at the levels of two categorical variables are independent or related

the probability of rejecting the null that is actually true. research directly control for the probability of committing this error by stating the level of significance

type 1 error

which error is for when we reject a true null hypothesis

type 1 error

a researcher reports no effect in the population, when in truth there is an effect. why type of error is this

type 2

which error is for when we retain a false null

type 2

the probability of retaining a null hypothesis that is actually false. the research is reporting no effect in the population, when in truth there is an effect

type 2 error

if the null is retained

we fail to reach significance

if the likelihood of obtaining a sample outcome is less than 5% if the null were true.....

we reject null because sample outcome would be unlikely to occur

when the p value is greater than .05

we retain null and state that an effect or difference failed to reach significance

what do we have to do in order to apply null hypothesis significance testing

we state a null hypothesis, then set a criterion upon which we will decide to retain or reject the null