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    IB Math AASL
    /
    Descriptive Statistics
    /

    Video

    Video Reviews

    Watch comprehensive video reviews for most units, designed for final exam preparation. Each video includes integrated problems you can solve alongside detailed solutions.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Descriptive Statistics

    Video Reviews

    Watch comprehensive video reviews for Descriptive Statistics, designed for final exam preparation. Each video includes integrated problems you can solve alongside detailed solutions.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Data & SamplesMeasuresVisualsRegression

    The video will automatically pause when it reaches a problem.

    Danger of extrapolation

    SL 4.4

    When using a regression line to predict y from x, we need to be aware of the danger of extrapolation. This occurs when we try to predict y for a value of x far outside the range of x values in our data. For such an x, we cannot trust that the relationship is the same.


    In our earlier example, we had data about the body temperature of babies in the first 12 months after birth. We had the regression equation:

    T=−0.05M+37.8


    It would be a foolish extrapolation to use this formula to predict the body temperature of an 80 year old... 80 years is 960 months, so

    T=−0.05⋅960+37.8=−10.2°C

    (a block of ice).

    Danger of extrapolation

    SL 4.4

    When using a regression line to predict y from x, we need to be aware of the danger of extrapolation. This occurs when we try to predict y for a value of x far outside the range of x values in our data. For such an x, we cannot trust that the relationship is the same.


    In our earlier example, we had data about the body temperature of babies in the first 12 months after birth. We had the regression equation:

    T=−0.05M+37.8


    It would be a foolish extrapolation to use this formula to predict the body temperature of an 80 year old... 80 years is 960 months, so

    T=−0.05⋅960+37.8=−10.2°C

    (a block of ice).

    Data & SamplesMeasuresVisualsRegression