
Inferential statistics are based on the laws of ____________ and are used to estimate population ________ from sample _________
 Probability
 Parameters
 Statistics

Given data from a sample, inferential stats allows us to _______________
Draw conclusions or make inferences about a population

Different researchers applying inferential statistics to the same data are likely to draw __________ conclusions.
the same

Inferentials stats assume _______ sampling from populations, assumption that is widely violated.
Random

________ is the tendency for statistics to fluctuate from one sample to another.
Sampling error

_________ is a theoretical distribution of a statistic, using the values of the statistic (the means) computed from an infinite # of samples as the data points in the distribution.
Sampling Distribution

What is a sampling distribution theoretical?
It is not actual because in practice no one draws consecutive samples from a population and plots their means.

When a distribution is normal _____ % of values fall between +,  1 SD from the mean, _____ % fall between =,  2 SD and _______ fall between =,  3 SD's..

The standard deviation of a sampling distribution of the mean is called ________
standard error of the mean (SEM)

The___________ is an estimate of how much sampling error there is from one sample mean to another.
SEM

If we increase our sample size, we ________ the accuracy of our estimates.
increase

Statistical inference consists of two techniques: ________ and ____________.
 estimation of parameters
 hypothesis testing

____________ is used to estimate a parameter
Parameter estimation

Examples of parameters are:
 a mean
 a proportion
 a mean difference btw groups

Estimation can take two forms:
 1. point estimation
 2. interval estimation

__________ involves calculating a single descriptive statistic to estimate the population parameter.
Point estimation

__________ estimation is useful because it indicated a range of values within which the parameter has a specified probability of lying.
Interval

The ___________ is the range of values within which a population parameter is estimated to lie, at a specified probability (e.g., 95 %__)
Confidence Interval (CI)

Confidence intervals reflect the researchers' _____________
risk of being wrong.

With a 95% CI, researchres aceept the probability that they will be wrong ____ times out of 100. A 99% CI, sets the risk of being wrong at _____.

For proportions based on dichotomous variables (positive or negative for a disease), the theoretical distribution is ___________
Binomial distribution

________ states that there is no relationship among the variables; that any findings are due to chance.
Null Hypothesis

A _________ error means that the Null Hypothesis was rejected, when in fact it was true.
*"False positive". We said there was a difference/effect when in fact, there was not.*
Type 1

A ______ error is made when researchers accept the null hypothesis when it fact it was NOT true.
This is a "false negative" conclusion. We said there is no difference, when in fact one exists.
Type 2.

A ________ error might prevent a good drug from coming to market.
A_________ error might allow an ineffective drug to come onto the market, while a

How do researchers control the risk of a Type 1 error?
By selecting a level of significance, which signifies the probability of incorrectly rejecting a true null hypothesis.

What is alpha?
Level of significance. Usually .01 or .05.

With a .05 alpha level, what is the risk of us incorrectly rejecting the null hypothesis?
5 out of 100 chance.

Lowering the risk of a Type 1 error can increase___________
the risk of making a Type 2 error.

The simplest way of reducing the risk of a Type 2 error is to ___________.
Increase sample size

Levels of significance are analogous to _____.
Whereby alpha of .05 =_______

What does the word significant mean in statistics?
Obtained results are not likely to be due to chance, at a specified level of probability.

What does a nonsignificant result mean?
An observed result could reflect chance fluctuations.

A onetailed test would be best when a ________ hypothesis is strongly suspected.
Directional

There are two broad 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, such as the assumption that the variables are normally distributed in the population.
Parametric

__________ tests, do not estimate parameters; they involve less restrictive assumptions about the shape of the variables' distribution than do __________
Nonparametric
Parametric

When the N is> 50, it may not be necessary to use ___________ statistics, unless the population has a markedly unusual distribution.
Nonparametric

What is the central limit theorem?
A statistical principle stipulating that the larger the sample, the more closely the sampling distribution of the mean will approximate a normal distribution and the mean of a sampling distribution equals the population mean.

When comparisons involve different people (men versus women), the study uses a _________ design and the statistical test is a ____________.
 Betweensubjects design
 Test for Independent groups

__________ statistical tests are used when there is only one group, that is used in multiple conditions (crossover designs).
Tests for dependent groups

What are the steps for testing a hypothesis?
 1. Select the appropriate test
 2. Establish the level of significance
 3. Select a 1tailed or 2tailed test.
 4. Compute a test statistic
 5. Determine the degrees of freedom
 6. Compare the test stat with a tabled value.

________ refers to the # of observations free to vary about a parameter.
Degrees of Freedom.

What is the parameter procedure for testing differences in group means?
ttest

What is an adjustment made to establish a more conservative alpha level when multiple statistical tests are being run from the same data set.
Bonferroni correction

When means for two sets of scores are not independent (dependent), researchers should use________
a paired ttest

VandeVusse et al. used ______ to assess changes in women's HR, RR and tensoin anxiety following exposure to a 30 min selfhypnosis intervention.
paired ttest

In certain 2 group situations, a nonparametric test may be needed. Two examples/reasons to use a nonparametric test are_____,_______
 1. if the dependent variable is on an ordinal scale
 2. If the distribution is markedly nonnormal.

The _________ test is the nonparametric analog of an independent group's ttest and involves assigning ranks to the two groups of scores. The sum of the ranks for the 2 groups can be compared by calculating the ____ statistic.

When ordinal level data are paired (dependent), the ________ test can be used. This test involves taking the difference between paired scores and ranking the absolute difference.
Wilcoxon signedrank.

_______ is the parametric procedure for testing differences between means when there are 3 or more groups by comparing variability between groups to variability within groups.
ANOVA

The statistic computed in ANOVA tests is _______
Fratio.

