Intro to Hypothesis Testing
In hypothesis testing, a statement that there is no difference between populations is the __________ .
Null Hypothesis
σ2M represents the __________ .
variance of the distribution of means
The test used to reach a decision about the null hypothesis when the population variance is unknown is the __________ test.
t
A population is normally distributed with μ = 50, σ = 8, and N = 10.
The mean of the distribution of means = __________ .
50
The variance of a distribution of means equals the variance of the population of individuals divided by _______________
the number of individuals in the sample, N, the sample size
Sometimes, a research hypothesis may be referred to as a(n) __________ .
df1 + df2 = __________ .
df total
Chi-square distributions are _________ skewed.
right or positively
A population is normally distributed with μ = 50, σ = 8, and N = 10.
If the sample mean is 45, the upper limit for the 95% confidence interval is __________ .
49.96
100 people are included in a study in which they are compared to a known population that has a mean of 73, a standard deviation of 20, and a rectangular distribution. σM = __________ .
2
A study is conducted to test a prediction that people who spend a great deal of time on the beach have more eye problems than people in general.
If Population 2 refers to people in general, Population 1 refers to ________ .
people who spend a great deal of time on the beach
The symbol "S2M2" represents _______________ .
the variance of the distribution of means for Population 2
If a psychologist interested in the effects of smell on concentration has 20 participants perform a standard task while exposed to an unpleasant smell and another 20 participants perform the same task without being exposed to the unpleasant smell, the appropriate test to analyze the data is a t test for __________ .
independent means
The sum of squared deviations from the mean for a sample is 12, and there are 4 participants. The estimated population variance is __________ . (Give a number.)
4
"S2pooled / N1" is the formula to find the variance of the __________ for Population 1.
distribution of means
A researcher wants to know whether people who listen regularly to radio talk shows are more or less likely to vote in national elections than are people in general.
The researchers would use a(n) ___ -tailed test.
Two
In a one-way analysis of variance, when sample sizes are equal, "(S2M)(n)" is the formula for ____________ .
the between-groups population variance estimate
The null hypothesis of an analysis of variance is that the __________ means are equal.
population
One hundred people are included in a study in which they are compared to a known population that has a mean of 73, a standard deviation of 20, and a rectangular distribution. σM = __________ .
2
"t = (M1 – M2) / S2difference" is the formula for a(n) _______ .
t test for independent means
Type I errors occur when a statistically significant result is obtained when in fact ________________ .
the research hypothesis is false and the null hypothesis is true
In a one-way analysis of variance, "(S21 + S22 + ... + S2last) / Ngroups" is the formula for_______________ .
the within-groups population variance estimate
In the chi-square test for goodness of fit, the degrees of freedom are __________ minus 1.
the number of categories
Assuming that the difference between two independent sample means is 6.24, and S2difference = 27, the calculated t score should be __________ .
1.20
In a one-way analysis of variance, when sample sizes are equal, "(S2M)(n)" is the formula for ____________
the between-groups population variance estimate