L14 - Presentation of Quantitative Data Flashcards
how are TABLES used to PRESENT QUANTITATIVE DATA?
when tables appear in the RESULTS SECTION of a RESEARCH REPORT they are NOT RAW SCORES but have been CONVERTED TO DESCRIPTIVE STATISTICS (MEASURES OF CENTRAL TENDENCY or MEASURES OF DISPERSION)
There should be a PARAGRAPH BENEATH THE TABLE EXPLAINING THE DATA
how are SCATTERGRAMS used to PRESENT QUANTITATIVE DATA?
A SCATTERGRAPH is a GRAPHICAL DISPLAY that shows the CORRELATION or RELATIONSHIP BETWEEN TWO SETS OF DATA (CO VARIABLES) by PLOTTING DOTS to REPRESENT EACH PAIR OF SCORES
A SCATTERGRAPH indicates the STRENGTH AND DIRECTION OF THE CORRELATION BETWEEN THE CO VARIABLES
how are BAR CHARTS used to PRESENT QUANTITATIVE DATA?
A BAR CHART is used to show FREQUENCY DATA for DISCRETE (SEPARATE) VARIABLES
E.g BAR CHARTS are used to PLOT MEAN SCORES for CONDITIONS A and B SEPARATELY
The HEIGHT OF EACH BAR REPRESENTS THE FREQUENCY of EACH ITEM. In a bar chart a SPACE IS LEFT BETWEEN EACH BAR to INDICATE THE LACK OF CONTINUITY. The FREQUENCY OF EACH CATEGORY is PLOTTED ON THE Y-AXIS
how are DISTRIBUTIONS used to PRESENT QUANTITATIVE DATA? - PT 1
with MOST DATA SETS the FREQUENCY OF THESE MEASUREMENTS should reflect a BELL SHAPED CURVE
This is called NORMAL DISTRIBUTION CURVE which is SYMMETRICAL. MOST PEOPLE (highest frequency) is located in the MIDDLE AREA of the curve and VERY FEW PEOPLE at EXTREME ENDS
The MEAN, MEDIAN and MODE all OCCUPY THE SAME MIDPOINT OF THE CURVE. The ENDS OF THE CURVE NEVER TOUCH THE HORIZONTAL X-AXIS as MORE EXTREME SCORES ARE ALWAYS THEORETICALLY POSSIBLE
how are DISTRIBUTIONS used to PRESENT QUANTITATIVE DATA? - PT 2
NOT ALL DISTRIBUTIONS form such a BALANCED SYMMETRICAL PATTERN. SOME DATA SETS derived from psychological scales or measurements PRODUCE SKEWED DISTRIBUTIONS, this is when distributions appear to LEAN TO ONE SIDE
A POSITIVE SKEW is when MOST OF THE DATA is CONCENTRATED to the LEFT OF THE GRAH, in this case the MODE REMAINS AT THE HIGHEST POINT OF THE PEAK, the MEDIAN COMES NEXT but the MEAN has been DRAGGED ACROSS TO THE RIGHT
The OPPOSITE OCCURS in a NEGATIVE SKEW
how else can we refer to POSITIVE/NEGATIVE DISTRIBUTIONS?
POSITIVE (RIGHT SKEW) - where is it SKEWED? ON THE RIGHT SIDE
NEGATIVE (LEFT SKEW) - where is it SKEWED? ON THE LEFT SIDE
how can we DIFFERENTIATE BETWEEN a POSITIVE AND NEGATIVE SKEW?
1) DRAW A DASH ON THE LOWER LEFT OF THE GRAPH, RIGHT AT THE START UNTIL ABOUT HALF WAY
2) DRAW A CIRCLE AROUND THE DASH
3) IDENTIFY WHICH OPERATION is IN THE CIRCLE - this is the type of SKEW YOU HAVE
