WEEK 11 Flashcards
The standard error of the differences between sample means serves as a rough indicator of the average amount by which
sample means deviate from tpopulation means.
The z test for two independent samples is hardly ever appropriate and hence ignored in the textbook – because it requires that both
population standard deviations be known.
“According to the guidelines for Cohen’s d, a value in the vicinity of .2 suggests that the estimated effect is”
small and could lack importance.
Which of the following research questions is best answered via an independent groups experiment?
are people who were born in the 1980’s less well behaved than people born in the 1940’s?
are males more aggressive than females?
are Australians more prone to developing skin cancer than the rest of the world?
does electromagnetic radiation increase the incidence of cancer in organisms?
does electromagnetic radiation increase the incidence of cancer in organisms?
“With reference to sampling, which of the following best describes the fundamental claim made in the null hypothesis for a hypothesis test about two independent populations?”
the two samples have been taken from populations that have the same mean
the two samples have been taken from the same population both a) and b) are equally valid options
the two samples have been taken from populations that have the same variance
both a) and b) are equally valid options
What factor should you take into account when deciding on what degrees of freedom to use to evaluate your obtained t statistic for the difference between two sample means?
the homogeneity of variances condition
“A lecturer wants to determine the effectiveness of on-line extra materials in assisting students in preparing for their final. They give on-line materials to the current trimester students, and compares their final’s scores with last year student’s scores. The same examination was given to both groups. What statistical test is appropriate here?”
independent t-test
What is the value for the mean of the sampling distribution of the difference between two means?
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