Statistics exam tips

Exam tips

• Statistical sampling exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to k1 Understand and use the terms population and sample; use samples to make informal inferences about the population; understand and use sampling techniques including simple random sampling and opportunity sampling; select or critique sampling techniques in context, including understanding that different samples can lead to different conclusions about the population..

  This keeps the answer actionable and aligned to Statistical sampling, rather than giving generic revision advice.

• Single-variable data diagrams exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to l1 Interpret diagrams for single-variable data, including understanding that area in a histogram represents frequency; connect to probability distributions..

  This keeps the answer actionable and aligned to Single-variable data diagrams, rather than giving generic revision advice.

• Scatter diagrams and regression lines exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to l2 Interpret scatter diagrams and regression lines for bivariate data, including recognition of scatter diagrams with distinct sections of the population; understand informal interpretation of correlation; understand that correlation does not imply causation; calculations involving regression lines are excluded..

  This keeps the answer actionable and aligned to Scatter diagrams and regression lines, rather than giving generic revision advice.

• Central tendency and variation exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to l3 Interpret measures of central tendency and variation, extending to standard deviation; calculate standard deviation, including from summary statistics..

  This keeps the answer actionable and aligned to Central tendency and variation, rather than giving generic revision advice.

• Outliers and data presentation exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to l4 Recognise and interpret possible outliers in data sets and statistical diagrams; select or critique data presentation techniques in context; clean data including dealing with missing data, errors and outliers..

  This keeps the answer actionable and aligned to Outliers and data presentation, rather than giving generic revision advice.

• Mutually exclusive and independent events exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to m1 Understand and use mutually exclusive and independent events when calculating probabilities; link to discrete and continuous distributions..

  This keeps the answer actionable and aligned to Mutually exclusive and independent events, rather than giving generic revision advice.

• Conditional probability exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to m2 Understand and use conditional probability, including tree diagrams, Venn diagrams and two-way tables; understand and use the conditional probability formula P(A|B) = P(A and B) / P(B)..

  This keeps the answer actionable and aligned to Conditional probability, rather than giving generic revision advice.

• Probability modelling exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to m3 Model with probability, including critiquing assumptions made and the likely effect of more realistic assumptions..

  This keeps the answer actionable and aligned to Probability modelling, rather than giving generic revision advice.

• Discrete and binomial distributions exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to n1 Understand and use simple discrete probability distributions, excluding calculation of mean and variance of discrete random variables; use the binomial distribution as a model and calculate probabilities using the binomial distribution..

  This keeps the answer actionable and aligned to Discrete and binomial distributions, rather than giving generic revision advice.

• Normal distribution exam tip 1

  Write the method before the answer so the examiner can follow each step. Apply this to n2 Understand and use the Normal distribution as a model; find probabilities using the Normal distribution; link to histograms, mean, standard deviation, points of inflection and the binomial distribution..

  This keeps the answer actionable and aligned to Normal distribution, rather than giving generic revision advice.