Week 3

Question 1

Statistics

Answer 1

Descriptive data from a sample

Question 2

Parameters

Answer 2

A samples corresponding values in the wider populations

Question 3

Sampling Error

Answer 3

The random variability in a statistic from sample to sample

Question 4

2 ways that a statistical relationship in a sample can be measured

Answer 4

• There is a relationship in the population and the relationship in the sample reflects this
• There is no relationship in the population and the relationship in the sample only represents sampling error

Question 5

Null hypothesis testing

Answer 5

Formal approach to deciding between interpretations of a sample

Question 6

Null Hypothesis

Answer 6

• No relationship in the population and the relationship in the sample is sampling error
• Chance relationship

Question 7

Alternative Hypothesis

Answer 7

• There is a relationship in the population and the relationship in the sample reflects this

Question 8

Reject the Ho

Answer 8

-A decision made by researchers using null hypothesis testing which occurs when the sample relationship would be extremely unlikely
- Researches always assume that the Ho is true

Question 9

Retain the Ho

Answer 9

A decision made by researchers in null hypothesis testing which occurs when the sample relationship would not be extremely unlikely

Question 10

P Value

Answer 10

The probability of the sample result/ a more extreme result if the null hypothesis were true

Question 11

High P value

Answer 11

Sample/ more extreme result would be likely if the Ho were true and leads to the retention of the Ho

Question 12

Low P Value

Answer 12

Sample/ more extreme result would be unlikely if the Ho were true and leads to the retention of the Ho

Question 13

Alpha

Answer 13

-The criterion that shows how low a p value should be before the sample result is considered unlikely enough to reject the ho
- Usually set to 0.05

Question 14

Statistically Significant

Answer 14

• An effect that is unlikely due to random chance and therefore likely represents a real effect in the population
• 5% chance or less; Ho rejected
• More than 5% chance; Ho is retained

Question 15

Role of sample size and relationship strength

Answer 15

• The stronger the relationship, the lower the p value
• The larger the sample size, the lower the p value

Question 16

Practical/ Clinical significance

Answer 16

• The importance/ usefulness of a result in the real world context

Question 17

Descriptive Statistics

Answer 17

Describes a typical response/ behaviour of a group as a whole

Question 18

Central Tendency

Answer 18

Indicators of the type of data that we can expect from the group as a whole

Question 19

Measures of central tendency

Answer 19

• Mean
  -Mode
  -Median

Question 20

Mean

Answer 20

-Add all values and divide by number of values
- May not be viable if you have an outlier

Question 21

Mode

Answer 21

• most common

Question 22

Median

Answer 22

Middle value when all the values are arranged in numerical order

Question 23

Dispersion

Answer 23

The variability or consistency in a set of data

Question 24

Measures of Dispersion

Answer 24

Range
Variance
Standard Deviation

Question 25

Range

Answer 25

-Calculated by finding the difference between the lowest and highest values in a set of data - Tells us nothing about the data in between

Question 26

Variance

Answer 26

- The mean of the squared difference between each of the values and the mean

Question 27

Types of Variance

Answer 27

- Sample Variance -Population Variance

Question 28

Standard Deviation

Answer 28

- Square root of variance - Measure of how far on average individual scores fall from the mean of a set of scores

Question 29

Measure of centre and spread for nominal data

Answer 29

- Mode - Number of categories containing values

Question 30

Measure of centre and spread for ordinal data

Answer 30

- Median - Interquartile Range

Question 31

Measure of centre and spread for interval data

Answer 31

- Mean - Standard Deviation

Question 32

Measure of centre and spread for ratio data

Answer 32

- Mean - Standard Deviation

Question 33

Confidence Intervals

Answer 33

-Give a range of values that may be plausible estimates of the population parameter -Can be calculated with different levels of confidence - The standard level is 95%