SG 6

Question 1

most common and most important distribution in statistics since many things are normally distributed.

Answer 1

Normal distribution

Question 2

A bell-shaped, symmetrical theoretical distribution, with the mean, median and mode coinciding at its peak and with frequencies gradually decreasing at both ends of the curve.

Answer 2

Normal distribution

Question 3

In a normal distribution, the _____ at any given point from the mean (as measured in s) will cut off exactly the same ______ of the total area

Answer 3

distance
proportion

Question 4

properties of Normal distribution

Answer 4

• Symmetrical about its mean
• Identical values for measures of central tendency
• Identical pattern of scatter, irrespective of the values of the mean or variance
• Regardless of the precise shape, the distance at any given point from the mean (as measured in s) will cut off exactly the same proportion of the total area

Question 5

any normally distributed variables can be converted to a standard normal distribution (t or f)

Answer 5

t

Question 6

A standardized normal distribution can be used to find the probability of a score occurring within that distribution (t or f)

Answer 6

t

Question 7

Values in a distribution are standardized using ____

Answer 7

z-scores

Question 8

These are transformed values that indicate the number of standard deviations a given value is above or below the mean.

Answer 8

z-scores

Question 9

distances of values from the mean in standard deviation units

Answer 9

z-scores

Question 10

A specific type of normal distribution that has 𝑥̅ = 0 and s = 1

Answer 10

standard normal distribution

Question 11

indicates that the raw value is greater than the mean

Answer 11

positive z-score

Question 12

indicates that the raw value is below the mean.

Answer 12

negative z-score

Question 13

Properties of the z-score:

Answer 13

• The sum of z-scores is zero
• The mean of z-scores is zero
• The standard deviation and the variance of z-scores is one