Duplicate of Week 5: Sampling Distribution

Question 1

Am I keeping up in PSYC123?

Accepted Answer

Almost

Question 2

Increasing the sample size of an opinion poll will reduce the…

Accepted Answer

variability of the estimates made from the poll data

Question 3

In a normal distribution, what % of scores fall within +/- 2 standard deviations of the mean?

Accepted Answer

95%

Question 4

Calculate estimate of the SD for the population? (Sample n = 10,X = 68,SS = 36)

Accepted Answer

2

Question 5

What is the z-score when X=60, μ=100, σ=15 Hint: z=(X-μ)/σ

Accepted Answer

-2.67

Question 6

A sampling distribution of the mean for random samples of n=5 from a given population is a

Accepted Answer

theoretical distribution of means of all possible n=5 sample

Question 7

The standard deviation of a sampling distribution of the mean is called the

Accepted Answer

standard error of the mean

Question 8

What is the standard deviation of the SAT Math Population distribution? (Graph appears shortly)

Accepted Answer

100

Question 9

To calculate an estimate of the population variance based on sample data, we use...

Accepted Answer

ŝ2 = SS/N-1

Question 10

The author of this quiz studied statistics from 1992 - 94. What didn’t she do during this time?

Accepted Answer

Neglected statistics

Question 11

What is the salary of a psychologist with z=2.5, μ=$70,000, σ=$12,000? Hint: z=(X-μ)/σ

Accepted Answer

$100,000

Question 12

Which of the following statements about z-scores is NOT true?

Accepted Answer

Z-scores cannot be calculated for Populations, only Samples

Questions 12