Definition 定義
Correlation is a statistical technique used to quantify the strength of relationship between two variables.
Used a lot in psychology investigations, for example Murstein (1972) carried out a correlation analysis of ratings of attractiveness in partners ('computer dance' study).
相關性是一種統計技術，用于量化兩個變量之間的關系強度。
在心理學調查中經常使用，例如，Murstein（1972）對伴侶的吸引力進行了相關分析（"電腦舞蹈 "研究）。
Strengths and weaknesses of correlation 相關性的優勢和劣勢
| Strengths 優勢: | Weaknesses 弱點 |
| Calculating the strength of a relationship between variables. 計算變量之間關系的強度。 | Cannot assume cause and effect, strong correlation between variables may be misleading. 不能假設因果關系，變量之間的強關聯性可能會産生誤導。 |
| Useful as a pointer for further, more detailed research. 作為進一步的、更詳細的研究的訓示器是有用的。 | Lack of correlation may not mean there is no relationship, it could be non-linear. 缺乏相關性可能并不意味着沒有關系，它可能是非線性的。 |
Analysis of correlation 相關性的分析
For a correlational study, the data can be plotted as points on a scattergraph. A line of best fit is then drawn through the points to show the trend of the data.
對于一個相關研究，資料可以被繪制成散點圖上的點。然後通過這些點畫出一條最佳拟合線以顯示資料的趨勢。
If both variables increase together, this is a positive correlation.
如果兩個變量一起增加，這就是一個正相關。
If one variable increases as other decreases this is a negative correlation.
如果一個變量随着其他變量的減少而增加，這是一種負相關。
If no line of best fit can be drawn, there is no correlation.
如果不能畫出最佳拟合線，就不存在相關關系。
Correlation can be quantified by using a correlation coefficient - a mathematical measure of the degree of relatedness between sets of data.
Once calculated, a correlation coefficient will have a value from -1 to +1.
相關性可以通過使用相關系數進行量化--這是一組資料之間相關程度的數學測量。
一旦計算出來，相關系數将有一個從-1到+1的值。
+1 = perfect positive correlation all points on straight line, as x increases y increases. A value close to one indicates a strong positive correlation.
+1=完美的正相關，所有的點都在直線上，随着X的增加，Y的增加。一個接近1的值表示一個強烈的正相關。
0 = no correlation points show differing degrees of correlation.
Note: A correlation around zero may disguise a non-linear relationship.
0 = 沒有相關的點顯示不同程度的相關。
注意：零左右的相關性可能掩蓋了非線性關系。
-1 = perfect negative correlation all points on straight line, as x increases y decreases. A value close to -1 indicates a strong negative relationship.
Note: In real life human situations, or psychology experiments you will not find perfect correlation between variables, life is just like that.
-1=完全負相關，所有的點都在直線上，當x增加時y減少。接近-1的數值表明有很強的負相關關系。
注意：在現實生活中的人類情況，或心理學實驗中，你不會發現變量之間有完美的相關性，生活就是這樣的。
What psychologists do is calculate a correlation coefficient, then, using statistical tables (thought up by brilliant mathematicians) work out the probability that their results could have occurred at random.
If they can say there is a 95% chance of their results really showing a strong correlation, then they accept that there is one.
心理學家所做的是計算相關系數，然後利用統計表（由傑出的數學家想出來的）計算出他們的結果可能是随機發生的機率。
如果他們可以說他們的結果有95%的機率真的顯示出強烈的相關性，那麼他們就接受有這樣的相關性。