Mock (Unit 1 & 2) Flashcards
Name the types of data, explain them and give examples?
Discrete = exact values e.g. # of people, shoe size, money (either have shoes size 6 or 6.5 not 6.73) Continuous = measured e.g. height where 164.4 is ok (decimal)
Difference between quantative and qualative data?
QUANTATive = numbers QUALATive = words
Explain the types of sampling and give e.g.?
SIMPLE = every member of the population has an EQUAL CHANCE of being included e.g. random number generator. Not a representative sample could be bias. STRATIFIED = population divided into STRATA where each STRATA is represented in the same proportion. CLUSTER = population divided into SUB GROUPS = CLUSTERS. These clusters are randomly selected and used instead of population. QUOTA = E.g. the interviewer is given a quota of types of people to interview.
What is the
Mean:
Median:
Mode:
Mean: + & divide
MeDian: miDdle
MOde: MOst
What does the lower/upper quartile, median min and max value look like on a calculator?
Lower quartile: Q1 Upper quartile: Q3 Median: MED Minimum: MIN Maximum: MAX
What is the interquartile range?
the amount in between the lower and upper quartile. MOST RELIABLE AS IT DOES NOT INCLUDE OUTLIERS
What is a Box Plot and what does include?
Used to see how data is spread on an axis. MIN L.Q I MED I.Q.R U.Q I MAX
What should you always mention when comparing box plots?
AVERAGE - MEDIAN (keyword average) (basically the median)
I.Q.R : is it compact (smaller than the other result) or spread (larger than the other result)
CONSISTENCY = size of I.Q.R is large = not consistent
LOWEST / HIGHEST result
How do you find the median (for box plots) on a calculator?
Menu , 6 , 1 , OPTN , 3
What does cumulative frequency refer to?
Running total - the graph tells us how many people had “up to this value”
What does cumulative frequency refer to?
Running total - the graph tells us how many people had “up to this value”. Used to present grouped data on a graph.
What should you always remember about a cumulative frequency graph?
Y axis = cum freq
Should always be curved
First set of data is plotted @ lower bound
Always plot the upper bound (9.9) e.g. 9.7 > t < 9.9
How do you calculate Cum frequency?
add each frequency e.g.
Frequency Cum freq
1 1
4 5
10 15
17 32
Why is a bar chart misleading and what should you replace it with?
A histogram because the area of the bars give a FALSE IMPRESSION RESULT. Instead, we use frequency density to present a more accurate representation
F.D = freq / width
width e.e. 0
How do we find frequency on a Histogram?
Area and frequency are in PROPORTION to each other = Area = frequency. Find out how many people each square is worth.
What does the standard deviation symbol look like?
OX
How do you calculate I.Q.R?
U.Q - L.Q
What are the characteristics of Income tax?
PAYE = taxed when your earn money
Higher salary higher tax
You get personal allowance
ALWAYS YEARLY
What are the characteristics of National Insurance?
ALWAYS MONTHLY
YOU HAVE TO WORK OUT THE MAX YOU CAN GET TAXED AT FOR EACH BOUND
What are the characteristics of Student loan?
ALWAYS YEARLY
9% charged after calculation
Answer this question: I put $1000 into a account with 3% interest p.a. How much is there in the account after 7 years?
$1000 x o.o3 power of 7 = $1229.89 after 7 years
What is APR and how do we calculate it?
Annual percentage rate.
C = loan amount A = amount YOU pay back I = APR expressed as decimal N = loan repaid over n years
What is the formula for calculating the loan amount and the APR?
loan amount = A/ (1+i) power n
n \_\_\_\_\_\_\_ APR = \/ A -1
C
What is the difference between a histogram and a cumulative frequency graph?
Cumulative Frequency = used with even grouped data (all the class widths are the same width) and when you’re comparing to another set of data.
Histograms = used with uneven grouped data e.g.
40 < w < 50
50 < w < 55
= uneven grouped data
What is AER?
Annual equivalent rate (saving)
What do you need to remember when calculating standard form?
The number can only be from 1 - 9.99
How do you find F.D and what is it used for?
HISTOGRAMS
frequency divided by width NOT THE OTHER WAY AROUND!!!!!!
Whats the difference between gross and net tax?
Gross = before tax Net = after tax "take home pay"
What is the formula for AER?
R = AER i = NOMINAL RATE (n x rate) N = # of compounding periods PER YEAR
What does Bi-weekly mean?
every other week = 26
What is needed to form a Fermi Estimation
Assumptions and Calculations
When net pay is mentioned, what deductions should be included?
Income tax
National Insurance tax
What is Census?
Surveying everyone in the population
What is it called when you survey everyone in the population?
Census
What is systematic sampling?
sampling every 5th or 10th item
What should be the ideal sample size?
Min 30
