Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
8 Cards in this Set
- Front
- Back
|
association
|
Values of one variable tend to occur with certain values of another variable; detected when the conditional distributions differ from the marginal distribution and from each other.
|
|
|
P-value
|
- Probability of obtaining a value of the statistic
- The value of the statistic is farther from the claimed parameter value than the observed statistic - The null hypothesis is assumed to be true. - probability of getting a test statistic as extreme or more extreme than the value observed assuming H0 is true - IS NOT PROBABILITY THAT THE NULL HYPOTHESIS IS TRUE. |
|
|
shape of non-normal sampling distribution of x-bar
|
- if n is large, shape is apporx. normal
- if n is small, shape is non-normal |
|
|
reject H-o
|
A. Results are statistically significant.
B. P-value < α. C. Conclude Ha is correct. D. The results are NOT due to chance. |
|
|
SIMPLE CONDITIONS FOR INFERENCE ABOUT A MEAN
|
1. We have an SRS from the population of interest. There is no nonresponse or other practical difficulty.
2. The variable we measure has a perfectly Normal distribution N(μ,σ) in the population. 3. We don’t know the population mean μ. But we do know the population standard deviation σ. |
|
|
CONFIDENCE INTERVAL FOR THE MEAN OF A NORMAL POPULATION
|
x-bar + or - Z-star times sigma/square root of n
|
|
|
CONFIDENCE INTERVALS: THE FOUR-STEP PROCESS
|
STATE: What is the practical question that requires estimating a parameter?
FORMULATE: Identify the parameter and choose a level of confidence. SOLVE: Carry out the work in two phases: (a)Check the conditions for the interval you plan to use. (b)Calculate the confidence interval. CONCLUDE: Return to the practical question to describe your results in this setting. |
|
|
test statistic (z)
|
x-bar - mu/sigma over square root of n
|
