Question | Answer |
What is the main purpose of the 95% CI for a mean? | To estimate the population mean |
How is the width of a CI for a mean determined? | The t-multiplier and the standard error of the estimate |
Heights of 18yer old students
Female: n = 10, m = 168 cm, s = 7.5
Male: n = 12, m = 180 cm, s = 7.25
What is an approxamite of the standard error of the difference between the sample means? | 0.28 |
Heights of 18yer old students
Female: n = 10, m = 168 cm, s = 7.5
Male: n = 12, m = 180 cm, s = 7.25
What is the degrees of freedom associated with the s.e. of the difference between the sample means? | 21 |
Heights of 18yer old students
Female: n = 10, m = 168 cm, s = 7.5
Male: n = 12, m = 180 cm, s = 7.25
What is the value of t for the CI of 95% for the entire sample size? | t = 2.08 |
Heights of 18yer old students
Female: n = 10, m = 168 cm, s = 7.5
Male: n = 12, m = 180 cm, s = 7.25
The 95% CI for m(F) - m(M) is (15.51, 8.49). Interprete it. | With 95% confidence we can estimate that the difference between the height of 18 year old men and the height of 18 year old women is somewhere bwtween 8.49cm and 15.51cm. |
What is the type of error associated with asking people to do an online survey. | Self-selection bias |
Selection Bias | When a group is surveyed that doesn't have a connection with the population of interest |
Self-selection Bias | When a group has the choice of replying to a survey |