Statistics

Question 1

National Curriculum/Teacher Framework/KS2 Test

Answer 1

Y1: No content
Y2: Tables/lists/diagrams/explaining choices not explicitly mentioned
Y3: Venn diagrams to sort data not mentioned
Y4: No need for specific Q, presentations, representations where scales have diff. step sizes
Y5: Probability - KS3
Removed need for ICT, data procedures, selecting/organsing data and und/interpreting mode not mentioned
Y6: Probability - KS3
No detail about data handling. Averages not mentioned - other than mean

For working at ES chl are expected to do a lot of what is no longer included in curriculum

Question 2

Testing

Answer 2

Measurement, Geometry + Stats only makes up 17-27 no. of marks (15-25%)
Stats: 
interpret/represent data
solve problems involving data
mean average

Question 3

Primary Data

Answer 3

Raw data collected by those who are going to analyse data

Question 4

Secondary Data

Answer 4

Collected by other people, already tabulated/summaried e.g. from cereal packets

Question 5

Discrete Data

Answer 5

Restricted to limited set of discrete values e.g. shoe size (6.3 doesnt exist) and money (cant have 32.87p)

Question 6

Categorical/Nominal Data

Answer 6

Arising from counts taken on a categorical (unordered discrete) variable e.g. favourite colour

Question 7

Oridnal Data

Answer 7

Order of values is important/signitificant but differences between each one not really known e.g. level of happiness from 1-10

Question 8

Continuous Data

Answer 8

Measures such as length, mass, time, temp. produce C.D - when measuring masses between 30g and 35g every possible value is available not just whole no.s

Question 9

Bar Chart/Histogram

Answer 9

B.C: Height = Frequency

H: Area of bars = Frequency

Question 10

Data Handling Cycle

Answer 10

Posing Q:
Plan/formulate Q in terms of data needed and what inferences may be made from them

Collecting the data:
Decide on way data will be collected - experiments, surveys, data from atlases etc.

Represent/Analyse Data:
Reduce raw data into sumary information including tables and charts to provide insight into P

Interpreting/Discussing Data:
Relate summarised data to initial Q’s and pose further Q’s that might be answered by data or may require addtional data to be collected.

Question 11

Data Handling Cycle - short

Answer 11

Specificy the P and plan
Collect data from variety of sources
Process and represent data
Interpret/Discuss data
Evaluate/Results

Question 12

Statistics Overall

Answer 12

Usually one off lessons - consider planning series of lessons
Choose topic for week, structure as many subjects around this as can
Consider displays, presentations - importance of stats
Explore bias, show how we represent someething can influence how someone interprets results

Question 13

Normal Distribution Curve

Answer 13

Mean, median, mode all lie in same place = identical

Mean is preferrred measurement

Question 14

Negatively skewed data

Answer 14

Mean dragged in direction of skew so median preferred measure
Test too easy=ceiling effect

Same for positively skewed data

Question 15

Mean

Answer 15

Add all no.s together and / by total e.g

6+3+100+3+13=125/5=25

Question 16

Median

Answer 16

Order no.s to find middle value e.g.
3,3,6,13,100 = 6 is middle value

If there are 2 middle no.s the median is halfway between them

Question 17

Mode

Answer 17

No. that appears most often

3,3,6,13,100 = 3 appears twice

Question 18

Range

Answer 18

Difference between highest/lowest value

100-3=97

Question 19

Box and Whisker Plots

Answer 19

3, 7, 7, 8, 9, 12, 14

3 = lowest no.
14 = highest no. 
8 = median
7 = first quartile (first 7)
12 = second quartile 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
|———-|–|————-|——-|
L.N Q.1 M Q.2 G.N

Work out range, G.N-L.N 14-3=11
Median =8