Statistics in Psychology GRE Scores

Questions and Answers

What percent of applicants scored above 450 on the GRE, given a mean of 544 and a standard deviation of 103?

82%

What is the percentile of a 33.40 millimeter diameter camshaft in a normally distributed population where 70% are greater?

30th percentile

What are the x-values for Q1, Q2, and Q3 in a normal distribution with a mean of 480 and standard deviation of 32?

458, 480, 502

What is the probability that a randomly selected person's z-score from a normal population would be above z=-1.8?

96% Signup and view all the answers

What is the GRE score at the upper quartile, Q3, for applicants with a mean of 544 and standard deviation of 103?

613 Signup and view all the answers

What is the z-score for the lowest quartile of any normal curve?

-0.67 Signup and view all the answers

What percent of applicants had a GRE score below 625, given a mean of 544 and a standard deviation of 103?

78% Signup and view all the answers

What percent of applicants scored between 500 and 700 on the GRE with a mean of 544 and standard deviation of 103?

60% Signup and view all the answers

What is the GRE score at the 77th percentile with a mean of 544 and standard deviation of 103?

620 Signup and view all the answers

What is the normal curve area, to the nearest whole percent, between z=-0.38 and z=+1.5?

58% Signup and view all the answers

Study Notes

GRE Scores in Psychology Applicants

GRE scores are normally distributed with a mean (m) of 544 and a standard deviation (s) of 103.
Score above 450: 82% of applicants scored above this GRE score.
Score below 625: 78% of applicants had a score below this threshold.
Score between 500 and 700: 60% of applicants scored within this range.
Upper quartile (Q3) score: The GRE score at Q3 is 613.
77th percentile GRE score: Calculated to be 620.

Camshaft Diameter Distribution

In a population of camshaft diameters, 70% exceed 33.40 millimeters.
A diameter of 33.40 millimeters is identified as the 30th percentile.

Quartiles in Normal Distribution

For a normal distribution with a mean of 480 and a standard deviation of 32:
- First quartile (Q1) x-value: 458.
- Second quartile (Q2 or median): 480.
- Third quartile (Q3) x-value: 502.
The z-score for the lowest quartile (Q1) is -0.67.

Probability and Z-Scores

If randomly selecting an individual from a normal population, the probability of obtaining a z-score above -1.8 is 96%.
The normal curve area between z=-0.38 and z=+1.5 is 58%.

Description

This quiz explores the statistical concepts related to GRE scores in psychology applicants, including normal distributions, percentiles, and quartiles. It also covers camshaft diameter distributions and their statistical properties. Test your knowledge of these essential statistical principles!