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Experimental Design

Aim: to investigate, outline the purpose, mention variables

Variables: any factor you have to consider within an investigation

  • Independent: variable we change on purpose

  • Dependant: variable that changes because of the independent (measure)

  • Controlled: variable that kept constant to prevent it affecting the results

  • Uncontrolled: variable that is not kept constant as it will not affect results (by accident don’t control, other times its by design)

Hypothesis:

  • 1 statement - prediction - educated guess

  • both independent and dependent mentioned and linked

Experimental group: experience the independent variable

Control group: don’t experience independent variable

Method:

  1. collect equipment

  2. setup equipment

  3. detailed enough to repeat

  4. replicates (multiple trials)

    • record data in table

    • Calculate average

Results: table - calculate average - graph (line, column)

Line: dependant variable on Y axis - use crosses

Column: dependant variable on Y axis - columns should have a space in between them (IV: words/description, numbers no decimals, numbers in range)

Conclusion:

  • restate your hypothesis

  • supported or not?

  • data to prove (minimum 2 points)

Discuss/Evaluate:

  • use scientific theory to explain what happened + why

  • trends in data

  • problem - talk about solution

Reliability: consistency of data - ex. 61bpm/65bpm/82bpm/62bpm

82bpm is the anomaly, either remove or retest

Accuracy: precision of results - ex. 100mL or 100.25/ ½ or 0.5

Validity: whether you tested what you intended to test (controlled variable

Different types of data

  1. Primary

    • collected yourself

    • time consuming and expensive

    • done in real time

    • more reliable

  2. Secondary

    • collected by others

    • quick + inexpensive

    • from the past

    • less reliable

Qualitative

  • descriptive

  • based on opinion

VS

Quantitative

  • numerical

  • based on fact

Experimental Design

Aim: to investigate, outline the purpose, mention variables

Variables: any factor you have to consider within an investigation

  • Independent: variable we change on purpose

  • Dependant: variable that changes because of the independent (measure)

  • Controlled: variable that kept constant to prevent it affecting the results

  • Uncontrolled: variable that is not kept constant as it will not affect results (by accident don’t control, other times its by design)

Hypothesis:

  • 1 statement - prediction - educated guess

  • both independent and dependent mentioned and linked

Experimental group: experience the independent variable

Control group: don’t experience independent variable

Method:

  1. collect equipment

  2. setup equipment

  3. detailed enough to repeat

  4. replicates (multiple trials)

    • record data in table

    • Calculate average

Results: table - calculate average - graph (line, column)

Line: dependant variable on Y axis - use crosses

Column: dependant variable on Y axis - columns should have a space in between them (IV: words/description, numbers no decimals, numbers in range)

Conclusion:

  • restate your hypothesis

  • supported or not?

  • data to prove (minimum 2 points)

Discuss/Evaluate:

  • use scientific theory to explain what happened + why

  • trends in data

  • problem - talk about solution

Reliability: consistency of data - ex. 61bpm/65bpm/82bpm/62bpm

82bpm is the anomaly, either remove or retest

Accuracy: precision of results - ex. 100mL or 100.25/ ½ or 0.5

Validity: whether you tested what you intended to test (controlled variable

Different types of data

  1. Primary

    • collected yourself

    • time consuming and expensive

    • done in real time

    • more reliable

  2. Secondary

    • collected by others

    • quick + inexpensive

    • from the past

    • less reliable

Qualitative

  • descriptive

  • based on opinion

VS

Quantitative

  • numerical

  • based on fact

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