How to Interpret Chi-squared test results

Chi-squared test is typically used for evaluating strength of association in scenarios where the measurement variables are categorical (example: vehicles classified as two-wheelers, four-wheelers etc.).  It's also a nonparametric test - in other words, it is "distribution-free".  Similar to how correlation coefficient helps interpret strength of association between real-valued variables, Cramer's V-score from Chi-squared test can be used with categorical variables. Degrees of freedom (df) for a chi-aquare distribution is 1 less than number of categories (df = number of categories - 1). Here's a handy table for how to interpret Cramer's V-score :

References:

1. Gravetter FJ, Wallnau LB. 'Essentials of Statistics for the Behavioral Sciences', 8th Edition. (see associated slide deck))