Sta 2381 - Study guides, Class notes & Summaries

Descriptive Statistics - correct answer used to organize, summarize, and describe data in a meaningful way. Ex: average salaries Inferential Statistics - correct answer Uses small subset (sample) data to make predictions/inferences about the real world (population). Ex: Pharmaceutical/drug studies Simple Random Sampling - correct answer Every ...

The independent-samples test is designed to measure _____________ between two samples that are independent of each other or two subsets within the same sample - correct answer Mean differences A ______________ t-test for two samples means is appropriate when we can assume that the population standard deviations are equal - correct answer Pooled variance Even if the means in the population are equa...

nominal - correct answer Naming or labeling (example: color of your eyes) Ordinal - correct answer being of a specified position or order in a numbered series interval/ratio - correct answer Ordering and exact distances Stages of Social Research - correct answer 1) Develop hypothesis 2)Develop instrum...

types of qualitative data - correct answer ordinal, nominal, dichotomous types of sampling - correct answer simple random, systematic, stratified, cluster systematic sampling - correct answer samples selected according to fixed interval stratified sampling - correct answer individuals randomly selected...

parameter: mu statistic: x bar - correct answer What variables are used for parameter and statistic of interest? Null: mu1 - mu2 = change alt: mu1 - mu2 > < no= change - correct answer testing hypothesis on the difference in means, variance known (What is the null and alternative hypothesis?) reject null (statistically significant) - correct answer ...

Which one of the following statements is TRUE? - correct answer As the alpha-level increases, the probability of a Type II error of a hypothesis test decreases. A pharmaceutical company has developed a new medication to lower a person's cholesterol. The advertisement for the new drug cites the results of an experiment comparing the drug with a placebo stating that the cholesterol level had been lowered by an average of 13.2 mg/l with a P-value &...

Hypothesis Statements are made about: - correct answer Population parameters Type I Error - correct answer Rejecting null hypothesis when it is true Probability of Type I Error - correct answer alpha Type II Error - correct answer failing to reject a false null hypothesis Probability of Type II Erro...

If we find that the differences between the sample mean is a rare event, we will conclude that - correct answer The null hypothesis is rejected For a study that contains 2 groups with a total of 18 participants, how many degrees of freedom are there for a dependent means t-test? - correct answer 17 (subtract 1 from the number) T or F- If the standard error of the difference between two samples is ...

mean for discrete random variables - correct answer ∑xP(x) variance for discrete random variables - correct answer ∑(x-µ)²P(x) exact probability for binomial distribution - correct answer ((n!)/((n-x)!x!))*p^x*q^(x-n) mean for binomial distribution - correct answer np variance for binomial dis...

What is the goal of hypothesis testing? - correct answer to test a hypothesis regarding a single mean ______________ is always located in the null hypothesis and the hypotheses are always in terms of the _________________. - correct answer Equality; parameters What are the three choices for the alternative hypothesis? - correct answer 1. u > u_o 2...