mathhhhh
DF for independent sample t
(n1-1) + ( n2-1)
which Alpha value has a lower risk of making a type 1 error
.01
which Alpha value has a lower risk of making a type 2 error
.05
if the null hypothesis is true, the Z for a sample mean, sample T Test, related samples T Test, all expect an obtained value close to
0
in most research situations in which a related samples T test is used the mean difference expected if the null is true is
0
when Computing the numerator of the independent samples T Test the population mean difference ( i.e U1-U2)will always be
0
if the null hypothesis is true, the Anova F value is expected to be close to
1
the effect size in this study indicates that the anti-anxiety drug raised cholesterol levels of the participants by how many standard deviations and is the effect size small medium or large
1.15 standard deviations large effect size
the first step in Computing a related samples T is to compute different scores (D) by:
Computing the D for each set of paired scores
you use a one-way independent measures Anova when
The IV defines two or more independent samples and the DV is on a ratio interval scale
you use an independent samples T statistic when
The Ivy defines two independent samples and the DV is measured on an interval ratio scale
what symbol represents a null hypothesis when doing a one tailed independent test
U1 >_ U2
what is the symbol that represents the null hypothesis when doing a two tailed independent test
U1=U2
which of the following best represents the null hypothesis for a two-tailed related samples T Test
Ud=0
which significance test should you use to determine if the difference between two unrelated samples is likely due to sampling error
Z for sample mean
when entering the data for an independent t-test you should have
a column for the IV and a column for the DV
why is it better to conduct an anova than multiple T tests when you're comparing multiple conditions
a single Anova helps keep the probability of type 1 error lower than doing multiple T tests
the null hypothesis for the independent Anova is that
all the sample means are the same
the estimated standard error of the mean difference is
an estimate of how different the two sample means are expected to be due to sampling error
an independent T Test can be used to compare differences between people that
are created by the researcher by providing different IV levels already exist in different populations of people
the research hypothesis for the independent and Nova is
at least one of the sample means is different from at least one of the other sample means
if the computed F value is greater than the critical value of f the null hypothesis should
be rejected
A major advantage of the Anova is that it can
compare the data from more than two conditions with a single analysis
the related samples T Test analyzes blank rather than blank
difference scores, raw scores
you use an independent Anova when you want to determine if the mean differences among two or more sample means are likely to be due to sampling error and you have
different people in each condition
to get a one tailed P value, you must
divide the two tailed P value in half
as with all types of T Test single sample and others if the null hypothesis is false the related samples T Test expects and obtained T value that is
far from zero
when you enter data for a related samples T Test you should:
have the paired scores on the same row of the spreadsheet
which of the following common statistical assumptions is not an assumption of the related samples T Test
homogeneity of variance
the levene's test will help you determine
if the two conditions have similar variances or variances that are very different IE the homogeneity of variance assumption is not met or violated
when determining if an effect size is small medium or large you should
ignore the sign of the computed effect size use absolute value
which significance test should you use to determine if the difference between two unrelated samples is likely to be due to sampling error
independent T Test
which sources of score variance can contribute to between treatment variance IE the numerator of an F ratio
individual differences measurement error and treatment effects all three
effect size for independent sample t
m1-m2 / sd2p square rooted
of the three sources of variance that can be potentially influential scores only two of them always influence scores which two will always influence the variability of scores
measurement error individual differences
when the obtained T value is not further from zero than the critical value the null hypothesis should:
not be rejected
if the obtained t value (IE in this case 2.83) is farther from zero than the critical value, the difference between the two means is:
not likely due to sampling error
when Computing the degrees of freedom for a RELATED samples T Test, the n in the formula is the:
number of pairs of scores
MSbetween is divided by the MSerror to produce the
obtained f value
which of the following is the best example of variability due to a treatment effect
people getting treatment may have lower depression scores than those getting treatment be because treatment a is more effective at helping depressed people
post hoc tests are needed whenever you
reject a Nova's null hypothesis and there were more than two independent variable conditions
an important distinction between the single sample t-test and the related sample t-test is that the blank analyzes mean differences between two sample means
related samples T Test
the two names for t test
repeated measures t test related samples t test
when you are doing a one-tailed tea test, the critical region is always on the side of the T distribution that is predicted by the
research hypothesis
the denominator of the f-ratio estimates the amount of variability createdbye
sampling error
the independent t-test is a ratio of the difference between two sample means over an estimate of
sampling error
which of the following values is a measure of sampling error
sem
two tailed research and null hypothesis are described with the key word :
significantly different
which of the following is the best example of variability due to individual differences
some people are more resistant to treatment for depression than others
if the null hypothesis is false the Anova F value is expected to be
substantially greater than 1
critical value for t test:
take the df and go to table and look up number
when Computing a related samples T Test you must remember that all of the analysis are done on
the difference between the paired scores for each participant ie (D)
Ud is the symbolic notation for
the mean of the difference scores from the population
when riding the reporting statement of the results the p-value is written as less than .05 because:
the obtained t value was in the critical region
whenever you fail to reject the null hypothesis and yet the effect size is medium or large you should conclude:
the sample size was too small and you should return the study with a larger sample size
when Computing the standard error of the mean difference, the equation calls for using
the sample sizes from each group
to compute the effect size you divide the observed deviation between the means by
the standard deviation of the difference scores
which of the following values can never be negative
the standard error of the mean difference
how do you interpret the effect size for Anova ieN2P=.22
the type of treatment people received explain to 22% of the variability in anxiety scores
the denominators of the single sample t-test and the related sample t-test are both blank
the typical amount of sampling error expected in the study
in research studies, researchers are most interested in evaluating which of the following sources of score variance
treatment effect
which source of score variance will never contribute to within treatment variance
treatment effects
what is the best example of variability due to measurement error
two people with the same level of depression produce different scores on a depression inventory
researchers use the related samples T test to determine if blank differ more than would be expected by sampling error
two related sample means
the numerator of the independent samples t-test is the difference between
two sample means
levene's test is automatically run by SPSS to determine if the blank of the two groups is significantly
variances
what are two things to do when interpreting the statistical results of any study?
you should consider if a confounding variable might have affected the results you should recognize that the experimental design is just as important to the scientific conclusion as the statistical result