Flashcards in Inferential Statistics Deck (63)
Data from samples are used to make inferences about what?
Researchers make what about an entire population based on smaller number of observations?
If many different samples were taken from a population, it would produce what?
Distribution of sample means
If different samples were taken an infinite number of times it would be called what?
What can be inferred from the sample?
The speed of means around the mean of a sampling distribution is called?
Standard Error of the Mean (SEm)
The standard error of the mean can be estimated from what?
SEm is higher when?
Sample SD is Large
Sample Size is Small
SEm is lower when?
SD is Small
Sample Size is Large
What type of SEm is preferred?
Smaller because it's more precise
What is a range of values that is likely to contain the population parameter that is being estimated?
Confidence Interval (CI)
The probability that this range of values contains the population parameter is typically what?
One can have a 95% confidence that the value of the true mean lies within the what?
What are the steps to calculating a CI?
1. Find the Z-score
2. Multiply Z-score by SEm
3. Add product to sample mean to find upper limit of CI
4. Subtract product from sample mean to find lower limit
What is related to the size of the sample and the size of the data variation?
Size of CI
A small sample and large variation causes what?
A large sample and small variable causes what?
What is an assumption that appears to explain certain events, which must be tested to see whether it is true?
What are the 2 types of hypothesis?
Hypothesis testing involves what?
Comparison of means of groups in an experiment
What is the objective of the hypothesis tests?
Find out whether they are significantly different from each other.
What will verify is the hypothesis is real?
The null hypothesis states that there is no difference between what?
The research hypothesis is accepted only if the null hypothesis is what?
Proves to be unlikely
What is unlikely to be due to chance?
Results of a study
Statistical significance at a specified probability level is referred to as?
Statistical significance must be at least 95% unlikely that the null hypothesis is true before what?
It can be rejected
P values must be equal to or less than 5% in order for results of a study to reach a level of what?
The level of significance is NOT the same as?