Chapter 1-4

Question 1

summation notation

Answer 1

The act of processing the sum

Question 2

Deviation score

Answer 2

The difference between an observation or value x and the mean value.

Question 3

Absolute deviation

Answer 3

The distance between each value in the data set and that data sets mean.

Question 4

Prediction vs criterion

Answer 4

The main difference between a criterion variable and a predictor variable is that a predictor variable is used to find the values of the criterion variable.

Question 5

Frequency distribution.

Answer 5

The pairing of the value of the variable with their associated frequencies.

Question 6

Histogram

Answer 6

The graphical representation of a frequency distribution.

Question 7

Symmetry

Answer 7

Where both sides of the frequency distribution are the same. Have a middle point that split both sides.

Question 8

Skew

Answer 8

Skew is the tail length on either side of the frequency distribution.

Question 9

Right skew

Answer 9

A tail that is longer on the right side.

Question 10

Left skew

Answer 10

A tail that is longer on the left side.

Question 11

Kurtosis

Answer 11

The shape of the distribution

Question 12

Platykurtic

Answer 12

A relative flat histogram.

Question 13

Leptokurtic

Answer 13

Skinny tails on both sides

Question 14

Mesokurtic

Answer 14

Between both flat and skinny tails

Question 15

Modality

Answer 15

Describes the number of peaks in a data set. Unimodal, bimodal, trimodal.

Question 16

Central tendency

Answer 16

A summation that attempts to describe a whole set of data with a single value that represents the middle or centre of its distribution

Question 17

Median

Answer 17

The value that cuts off the bottom 50% of the he score

Question 18

Mean

Answer 18

The total of the scores divided by the number of scores

Question 19

Deviation and distance

Answer 19

The distance and direction an individual value of x is from the mean of all the x’s.

Question 20

ADD-absolute average deviation

Answer 20

Average distance scores are from the mean

Question 21

Var- variance

Answer 21

The average squared distance scores are from the mean.

Question 22

Standard deviation.

Answer 22

The square root of the average square scores are from the mean.

Question 23

Range

Answer 23

The area of variation between upper and lower limits on a particular scale. Highest to lowest distance.

Question 24

Location of CT vs spread

Answer 24

The mean can stay the same, as long as the spread is consistent.

Question 25

Conditional distribution

Answer 25

It’s the distribution of one variable upon one level of another variable. The more the difference, the bigger the correlation. Skews etc

Question 26

The covariance

Answer 26

The value that one variable corresponde with another. When a value is the same as the mean it has zero covariance.

Question 27

Pearson R

Answer 27

The linear correlation between two variables, measured on a scale of standard deviation.

Question 28

Correlation coefficient

Answer 28

Index of linear and non linear only when it’s bounded. As in between -1 and 1.

Question 29

Invariant

Answer 29

A function, quantity, property which remains unchanged when a specified transformation is applied.

Question 30

Outliers

Answer 30

Any value that has a large influence on the value of a statistic calculated on a set of data. Careful with mean instead use median.

Question 31

Parameter

Answer 31

A characteristic that describes the population, which will be the average.