1. Introduction - Variability and Sampling Populations

Question 1

Why do we need statistics?

Answer 1

It describes a situation to us and gives us facts about a given topic.

Question 2

Displaying data

Answer 2

From complex to simple.

Example:
List of data with various complex numbers, easier to understand in graph.
Find a way to represent his data that has meaning to us.

Question 3

Histogram

Answer 3

different to a Bar chart.

On the x-axis (independent variable) - like a scaler - number at the front is larger and the number at the back is smaller. Align things in order - order the data that might not be ordered into something meaningful.

Y-axis (dependent variable) - increase of repeated numbers from x-axis. The more something occurs on the x-value, the lager the y-value is.

Question 4

Independent Variable

Answer 4

Something the scientist controls and can be varied as I see fit.

Question 5

Dependent Variable

Answer 5

Depends on independent Variable. Depends on the value obtained from the independent variable.

Question 6

Bell-shaped Curve

Answer 6

Very important!!

A way of describing data as being normally distributed.

Question 7

Significance

Answer 7

Ordered the data to look for something normal which would give us significant values.

Applied a statistical test which would give us a result of value and significance.

Question 8

Ho to decide to trust your Data?

Answer 8

Correct labelling of axis.

Correct display of error bars.

Question 9

Error Bar

Answer 9

The error is something I can’t account for.

Big error bar - Data is highly variable and cant be confident in it. Wouldn’t want to present due to lack of trust.

Small error bars - trustworthy and something presentable

Question 10

Correlations

Answer 10

Looking for relationships between data.

Example:
Amount of x-axis correlating with the happiness on y-axis? -> power point sweets slide

Linear relationship - data displayed in a straight line

Question 11

Positive correlation

Answer 11

value increases further along on x-axis.

Question 12

Negative correlation

Answer 12

value decreases across the x-axis.

Question 13

Descriptive Statistics

1. ) measure of central tendency
2. ) measure of variability

Answer 13

Brief, descriptive co-efficient which summarise a given data set. This can be a representation of the entire or a sample of a population.

They are broken down into messures of central tendency and measures of variability (spread).

1.) this is a summary statistic, representing the centre point or typical value of a data set.
The three most common measure of central tendency are the mean, median and the mode. Each calculates the location of the central point using a different method.

2.) the most common are the range, variance, and standard deviation.